Publish PerchApp and install it from the one-line installer

[Jing-yilin]

Summary

Publish the native macOS PerchApp menu bar app as a GitHub Release artifact and update the one-line installer so it can automatically install/update the app alongside the perch CLI.

Current state:

• v0.1.0 publishes only CLI binaries and checksums.
• install.sh installs the CLI and agent /perch commands, then only opens PerchApp if it already exists locally.
• Features such as menu bar grouping by project path exist in source, but normal one-line install users do not receive a PerchApp binary.

Goals

• Release PerchApp for macOS as a downloadable artifact.
• Make the one-line installer install/update PerchApp automatically by default on macOS.
• Preserve existing Perch storage at ~/.config/perch/.
• Keep the CLI install flow non-interactive and idempotent.

Proposed Release Artifacts

Minimum viable artifacts:

• PerchApp-aarch64-apple-darwin.zip
• PerchApp-aarch64-apple-darwin.zip.sha256
• PerchApp-x86_64-apple-darwin.zip
• PerchApp-x86_64-apple-darwin.zip.sha256

Preferred contents:

• A proper Perch.app bundle if feasible.
• If bundle packaging is not ready, a zipped PerchApp executable is acceptable as an MVP, installed under ~/.local/share/perch/PerchApp or similar.

Future hardening:

• Sign and notarize .app bundle.
• DMG packaging.
• cosign/GitHub artifact attestations.

Installer Behavior

Update install.sh to:

1. Install the perch CLI as it does today.
2. Detect macOS architecture.
3. Download matching PerchApp artifact and .sha256 from latest GitHub Release.
4. Verify SHA-256 before unpacking/installing.
5. Install app to a stable location, e.g. one of:
   • /Applications/Perch.app if permissions allow and user opts in.
   • ~/Applications/Perch.app as default for app bundle.
   • ~/.local/share/perch/PerchApp if shipping raw executable MVP.
6. Open the installed app after successful install unless disabled.
7. Print clear summary and troubleshooting hints.

Suggested environment flags:

PERCH_INSTALL_APP=1        # default on macOS once artifacts exist
PERCH_INSTALL_APP=0        # skip app install
PERCH_APP_INSTALL_DIR=...  # override destination

CLI Integration

This pairs with issue #6:

• perch menubar start
• perch menubar stop
• perch menubar status
• perch menubar login enable|disable|status

Once the app is installed by install.sh, these commands can reliably find the installed app path.

Non-goals

• Do not delete or migrate ~/.config/perch/sessions.json.
• Do not require Rust/Swift toolchains on user machines.
• Do not require signing/notarization for the MVP unless needed by macOS Gatekeeper behavior.

Acceptance Criteria

• GitHub Release workflow builds PerchApp for macOS arm64 and x86_64 or documents a universal build choice.
• Release includes app artifacts and .sha256 files.
• install.sh downloads and verifies the matching app artifact.
• install.sh installs the app to a stable user-accessible location.
• install.sh opens the installed app after install by default.
• PERCH_INSTALL_APP=0 skips app installation.
• Re-running installer updates app idempotently without deleting Perch storage.
• README documents CLI + menu bar app installation behavior.
• Tests cover app artifact download/checksum/install path selection where practical.

[Jing-yilin]

Completed and released. The one-line installer now installs the CLI and PerchApp bundle from v0.1.2 artifacts while preserving existing storage.