kache 0.2.0

The first release we're comfortable promoting widely. Local content-addressed caching with hardlink-based restoration is stable; direct kache sync to S3-compatible backends has been in production for months. The remote prefetch planner is still SOON.

What's Changed

• docs(readme): add demo + monitor GIFs, reframe WIP server as SOON by @jleni in #38
• docs: pre-launch onboarding pack (CI, contributing, templates) by @jleni in #39
• chore: pre-0.2.0 polish — Cargo.toml metadata + tighter README description by @jleni in #41

Full Changelog: v0.1.1...v0.2.0