v0.6.7-alpha — hitch fix release

The headline: micro-freezes during gameplay are fixed

Field diagnostics from v0.6.6 showed the emulator thread stalling for
player-visible instants whenever the background live compiler finished or
started a run — the "occasional hitches" reported during fights. All of that
maintenance work (compile-log scans, shard-cache rescans, snapshot manifest
writes, compiler process launches) now runs on a dedicated worker thread. The
emulator thread keeps only the cheap parts.

Stress-tested at roughly 30x the real-world compile cadence: the worst
emulator-thread stall drops from ~25 ms/frame to under 4 ms/frame, with
byte-identical compile results and identical shard loading behavior.
Menus may also feel slightly snappier — the per-frame polling overhead is
lower even when nothing is compiling.

Also in this release

• The ARM7 bank registration order shipped in this build now matches the
  intended design (the WRAM alias registers first). Previous releases
  silently used plain alphabetical order. Local multiplayer holds a flat
  60 fps in the automated check on this build.

Upgrade notes

• Same as v0.6.6: no prebuilt native shard cache in the package. If you are
  upgrading, copy your existing live-shard-cache directory across to keep
  your accumulated shards — they load fine under this runner.
• Save files and settings carry over unchanged (no settings migration in
  this release).

Checks run on this exact build

• 22/22 runner test suite, 251/251 bank inventory, DLL import closure clean
• PGO-optimized runner (57 training profiles)
• Owner play-tested multiplayer on the staged package before publishing

SHA256 (zip): 95AB6850798BC270733CB019A458C9C286EA84017F44BF5B0A2207275ED3D8AE