feat: version-aware find-browse with META signal protocol

Agents in other workspaces found stale browse binaries that were missing
newer flags. find-browse now compares the local binary's git SHA against
origin/main via git ls-remote (4hr cache), and emits META:UPDATE_AVAILABLE
when behind. SKILL.md setup checks parse META signals and prompt the user
to update.

- New compiled binary: browse/dist/find-browse (TypeScript, testable)
- Bash shim at browse/bin/find-browse delegates to compiled binary
- .version file written at build time with git commit SHA
- Build script compiles both browse and find-browse binaries
- Graceful degradation: offline, missing .version, corrupt cache all skip check

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "gstack",
-  "version": "0.3.1",
+  "version": "0.3.2",
   "description": "Garry's Stack — Claude Code skills + fast headless browser. One repo, one install, entire AI engineering workflow.",
   "license": "MIT",
   "type": "module",
@@ -8,7 +8,7 @@
     "browse": "./browse/dist/browse"
   },
   "scripts": {
-    "build": "bun build --compile browse/src/cli.ts --outfile browse/dist/browse",
+    "build": "bun build --compile browse/src/cli.ts --outfile browse/dist/browse && bun build --compile browse/src/find-browse.ts --outfile browse/dist/find-browse && git rev-parse HEAD > browse/dist/.version",
     "dev": "bun run browse/src/cli.ts",
     "server": "bun run browse/src/server.ts",
     "test": "bun test",