feat(cli): publish no-JRE jar bundle + Homebrew-core formula for amy

Enable distributing the `amy` CLI via Homebrew-core (mainline formulae).
Homebrew-core builds in a network-sandboxed env, so a from-source Gradle
build can't resolve Maven deps there; the accepted pattern for JVM tools is a
pre-built no-JRE jar bundle + `depends_on "openjdk"`. installDist already
produces exactly that (bin/amy + lib/*.jar, no bundled runtime).

- create-release.yml: publish `amy-<version>-jvm.tar.gz` (the installDist tree)
  as a release asset on the linux leg. Pure JVM bytecode, so one
  platform-independent artifact serves every OS.
- packaging/homebrew/amy.rb: reference formula (depends_on openjdk, livecheck
  for BrewTestBot auto-bumps, `amy --help` smoke test). Not consumed by any
  build here — it's the artifact to submit to Homebrew/homebrew-core.
- BUILDING.md: homebrew-core submission runbook; note that the desktop app is
  already on mainline Homebrew (homebrew/cask); document name-collision and
  pre-built-jar review caveats.
- asset-name.sh: document the jvm bundle naming exception.

Verified locally: :cli:installDist builds with only a JDK (no Android SDK),
and the extracted bundle runs via JAVA_HOME (`amy --help` exits 0).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015sso31DfSF9B6EFCVkEqWD

.github/workflows/create-release.yml

@@ -321,6 +321,23 @@ jobs:
           source scripts/asset-name.sh
           collect_cli_assets "${{ matrix.family }}" "${{ matrix.arch }}" "${{ steps.ver.outputs.version }}" dist
 
+      # Homebrew-core ships a no-JRE jar bundle and depends_on "openjdk" — it
+      # cannot use the jlink tarball above (bundled runtime) nor build from
+      # source (its sandbox blocks Gradle's Maven downloads). installDist
+      # (bin/amy + lib/*.jar, no runtime/) is exactly that bundle. It is pure
+      # JVM bytecode, so one platform-independent asset serves every OS; we cut
+      # it on the linux leg only. amyImage depends on installDist, so the
+      # cli/build/install/amy tree already exists here.
+      - name: Package no-JRE jvm bundle for Homebrew (linux leg only)
+        if: matrix.family == 'linux'
+        run: |
+          set -euo pipefail
+          VER="${{ steps.ver.outputs.version }}"
+          SRC="cli/build/install/amy"
+          test -x "$SRC/bin/amy"
+          ( cd "$SRC" && tar czf "$OLDPWD/dist/amy-${VER}-jvm.tar.gz" bin lib )
+          echo "Collected: dist/amy-${VER}-jvm.tar.gz"
+
       - name: Enforce CLI size budget (200 MB per asset)
         run: |
           set -euo pipefail