Release v0.2.6 — Workspaces, Minimal Theme, AI in Diagrams

Workspace folders, a brand-new Minimal theme, AI editing for Mermaid diagrams, a near-WYSIWYG PDF export — the editor finally feels like a place you can stay in for hours, not just a quick-note tool.

Workspaces

• Multi-root workspace sidebar (#69) — open one folder, two folders, ten. Each gets a collapsible section with file tree, drag-to-reorder header, and per-workspace controls (search, new file, open folder, menu). The active workspace shows a colored dot.
• Folder tree like Zettlr / Obsidian — expand / collapse subdirectories, click a file to open in a new tab, right-click for OS-level reveal, rename, delete, new file / folder. Expanded folders are remembered between sessions.
• AI sees the workspace — when a file lives inside an open workspace, the AI preamble includes the workspace root as a read-only scope. Ask "summarize the meeting notes from the last two weeks" and the model can actually traverse the folder; writes still stay scoped to the active document.
• Quick switcher — Ctrl+Shift+E opens a 3-section command palette: workspaces, files (filename match), content (full-text grep across the active workspace, debounced 150 ms, capped at 5 000 files / 4 s / 200 hits so it never stalls a big tree).
• Migration from v0.2.x — existing lastRoot workspace settings are auto-migrated to the new openWorkspaces[] shape on first launch.

Minimal theme

• Mermaid-logo palette — teal #14b8a6 and coral #f43f5e over slate #1a2028. Light and dark variants both ship; the variant axis is orthogonal to light/dark, so any combination works (Default + Light, Default + Dark, Minimal + Light, Minimal + Dark).
• Editor chrome only — accents live in tabs, sidebar headers, the active workspace dot, the AI status indicator. The document content stays neutral so prose doesn't fight for attention with the chrome.
• Configurable padding — Settings → General now exposes top, side, and bottom padding sliders. Values apply to both Default and Minimal themes (the previous build only wired them up for Minimal).
• Better code blocks in Minimal — dark slate background with full syntax highlighting, instead of the previous flat grey selection look.
• Full-width horizontal rules — --- now spans the full content column.

AI in Mermaid diagrams

• Edit via the main AI panel — clicking the AI button on a diagram (or in fullscreen edit) registers a target with the panel, auto-pins the diagram source as scoped context, and switches the preamble into mermaid-edit mode. You get the full panel: model picker, multi-turn conversation, threads, snapshots — same surface you use for prose.
• Live preview, explicit Apply — every assistant reply is parsed for a mermaid fenced block. The diagram renders the proposal in place, with a chip in the panel showing Apply ✓ / Discard × / Stop. Apply commits to the node attrs; Discard keeps the conversation going; Stop ends the session.
• Coexists with fullscreen edit — you don't have to leave the fullscreen mermaid editor to use the AI. The panel sits on top (z-index: 100000) so both stay visible; minimising the chat restores the diagram to full width.
• Robot icon, no more star — the diagram AI button uses the same robot glyph as the main toolbar, so it's recognizable across the app.

PDF export — closer to WYSIWYG

• Match the editor — the PDF now uses the same serif font (Charter / Iowan Old Style / Palatino) at the same scale (11.5 pt / 1.7 line-height) as the Minimal editor. What you see really is what you get.
• Editor padding → PDF margins — your top / side / bottom padding settings are applied as body padding inside @media print, so a tight editor prints with tight margins and a roomy editor prints generously. The fixed @page margin (10 mm safety) layers on top of that.
• Code blocks keep their colours — One-Dark palette (keyword purple, string green, number / attribute orange, comment grey, …) renders inside the PDF with -webkit-text-fill-color set explicitly so Chromium's PDF backend doesn't strip the colour. Background stays dark slate.
• Inline code matches the editor — coral text (#e11d48) on light grey, mirroring the Minimal theme's --danger-tinted inline code instead of the previous teal that diverged from both on-screen variants.
• Tables size to content — switched from table-layout: fixed (which spread one-word columns and long-URL columns to equal widths) to auto, so a Method | Route | Handler table reads the way it does in the editor.
• Hidden chrome, real layout — the workspace sidebar collapses to zero width (not just display: none, which left a flex reservation), all dialogs / overlays / drag artefacts are gone, the document fills the printable width 1:1.
• No more dark-mode bleed — earlier builds had html.dark[data-variant="minimal"] selectors out-ranking the print overrides; the print block now hard-pins the entire container chain to white with hex #ffffff instead of relying on cascading --bg-primary.

UI polish

• Resizable Mermaid editor split — the divider between code and preview in fullscreen mermaid edit is draggable; the ratio is persisted into the markdown via node attrs (splitRatio) and survives roundtrip.
• Resizable diagram in document — drag the right edge of an inline mermaid block to set a custom width; persisted as userWidth.
• Word-style zoom slider — the editor zoom (Ctrl + Scroll, Ctrl+/-) now has a visible slider in the status bar with ± buttons and percentage readout. Cleaner than the dropdown that lived there before.
• Tab pin + context menu — right-click a tab for Pin / Unpin / Close / Close others / Close all but pinned / Close saved / Close all. Pinned tabs reorder to the front and survive bulk-close.
• Quick switcher with content search — files and live full-text grep across the active workspace, behind Ctrl+Shift+E.
• Split file-ops button — the toolbar + is now two buttons: "New file" and "Open folder", so the workspace flow is one click instead of two.
• Styled prompts and confirms — the native window.prompt / window.confirm modals are replaced with themed dialogs everywhere (rename file, delete file, conflict resolution, …).

Bug fixes

• os error 123 on Windows when the AI is asked to edit a fresh / unsaved file — both claude and codex were getting an empty work_dir which Windows rejects on Command::current_dir. The Rust spawn helpers now fall back to $HOME / $USERPROFILE / . when the work dir is empty.
• codex --cd "" rejection — same root cause on the codex side; --cd is now only set to a real path, and --add-dir is skipped when no work dir is known.
• Claude / Codex CLI on macOS / Linux (#70 — also in 0.2.3) — GUI launches inherit a minimal PATH so installs from Homebrew / npm-global / volta / nvm / bun / asdf were not detected. The resolver now walks a curated list of standard install dirs and falls back to a login-shell probe ($SHELL -lc 'command -v <name>'); Settings → AI → CLI exposes a custom-path override with the actual list of locations the app searched, so you can see what was tried.
• AI mermaid modal not appearing on first click — nested <Teleport> inside the editor fullscreen sometimes failed to mount; the modal renders in place now (and as of this release is replaced by the main AI panel anyway).
• PDF dark-mode bleed — multiple iterations to defeat scoped Vue styles + html.dark[data-variant] rules; the entire container chain is now hex-pinned to #ffffff in print.
• PDF top margin too large in Minimal — Minimal's padding-top: 32px stacked on top of the @page :first margin and gave a 2 cm gap; print now zeroes editor padding and uses body padding routed from your editor settings.
• Autolink URL appendix — TipTap autolinks CLAUDE.md into <a href="http://CLAUDE.md">, and the previous a::after { content: " (" attr(href) ")" } rule then printed CLAUDE.md (http://CLAUDE.md) next to every plain-text mention. The URL appendix is gone; PDFs embed real hyperlinks anyway.
• Mermaid <select> % dropdown jankiness — the native dropdown stole the popup layer inside the floating toolbar and the active option visually shifted on every render; replaced by four buttons (25 / 50 / 75 / 100).
• Default mermaid scale 25 → 100 — new diagrams render at full size by default; the previous 25 % default left them tiny in the document.
• Workspace sidebar visible in PDF — display: none left a flex width reservation; the sidebar now collapses with width: 0; visibility: hidden.
• AI panel tab visible in fullscreen mermaid edit — when minimised during a mermaid AI session, the tab needs to sit above the diagram fullscreen overlay. z-index: 100000 is now applied conditionally so it only outranks the overlay during an active mermaid edit.
• Claude AI on Windows — batch file arguments are invalid (from 0.2.5) — Claude CLI resolves to claude.cmd (npm shim); Rust 1.77+ rejects .cmd invocations with newline-bearing args (CVE-2024-24576 mitigation). The system preamble is multi-line. Spawn now uses the documented --input-format stream-json path universally and folds the preamble into the user message text — same pattern as the Codex spawn.
• Codex error events surface in the chat (from 0.2.5) — Codex's top-level error / turn.failed envelopes were being dropped by the stdout normalizer; users got a generic "AI process exited without finalising the turn" instead of the real reason (e.g. "The 'gpt-5' model is not supported when using Codex with a ChatGPT account."). The normalizer now matches both shapes and unwraps the upstream API message.
• Last-stderr tail attached to "exited without finalising" errors (from 0.2.5) — when an AI child genuinely dies without emitting a final JSON event the synthesised error chunk now includes the last 20 lines of the child's stderr so you don't need a debug build to diagnose it.
• Settings → AI shows resolved binary path (from 0.2.5) — under the version line for each CLI you can see the actual path the resolver picked (C:\Users\…\AppData\Roaming\npm\claude.cmd, /opt/homebrew/bin/codex, your custom override, …). Makes it obvious which install is in use.
• Right-click open (#73, from 0.2.4) — context-menu Open with MerMark on Windows now actually opens the file instead of failing silently.
• Drop file from workspace tree onto split pane — drag a file out of the sidebar onto the left or right pane in split mode and it opens there. Works on empty panes too. Capture-phase listeners outrank TipTap/ProseMirror's own dragover handler so the cursor doesn't stick in not-allowed.
• Click on workspace file with zero tabs open — after Close All, clicking a workspace file used to do nothing because loadFileIntoTab short-circuited on findActiveTabIndex() === -1. Falls through to createNewTab now.
• Window stays open after Close All when a workspace is open — closing the last tab no longer terminates the window when at least one workspace is loaded; the sidebar stays useful for browsing, dragging, and quick-switching.
• Typing lag on big docs — useToolbarActions is called by ~20 components (Toolbar / LeftBar / StatusBar / each ToolbarItemRenderer); each used to register its own editor.on('update') listener that ran getHTML + htmlToMarkdown + token recount. With many tables / code blocks this stalled typing for hundreds of milliseconds per character. Listener + token counter hoisted to module scope (one per editor); typing is responsive again.

Under the hood

• AI CLI path cache — once a claude / codex binary is resolved, the path is stored in settings (cliResolvedPathClaude / cliResolvedPathCodex) and reused on subsequent probes. Cold-start health checks are now near-instant on machines where the resolver had to do a login-shell probe.
• Settings migration — useSettings deep-merges new fields on load (editorPaddingTop / Bottom / X, openWorkspaces[], activeWorkspaceId, cliResolvedPath*), so existing installs upgrade without losing anything.
• Markdown roundtrip for mermaid attrs — node attributes (userWidth, splitRatio, printScale) survive markdown serialization via a <!--mermaid-attrs:k=v,…--> HTML comment immediately before the fenced block, parsed back into TipTap node attrs on load.
• useAiMermaidTarget singleton — clean bridge between the diagram node and the AI panel. The node only registers a target with apply and cancel callbacks; the singleton tracks the candidate and exposes applyCandidate / discardCandidate / clear. Adding new "AI edits this kind of node" surfaces will use the same pattern.
• useToolbarActions listener deduped — Toolbar / LeftBar / StatusBar / every ToolbarItemRenderer call site used to register its own editor.on('update') handler, so each keystroke ran ~20 copies of getHTML + htmlToMarkdown + token recount. The listener and the token counter are now hoisted to module scope (one per editor); typing on docs with many tables / code blocks no longer stalls.