feat(ui): launch at login and harden menu popover

Formula/microbridge.rb

@@ -101,7 +101,8 @@ def caveats
         Status:  microbridgectl status
         Config:  ~/.microbridge/
 
-      Start the service once to install the marker-owned app, then open it:
+      Start the service once to install the marker-owned app, then open it. The
+      app will offer to start itself at login (change it in Settings > General):
         brew services start microbridge
         open ~/Applications/Microbridge.app
 

INSTALL.md

@@ -132,6 +132,15 @@ Tauri build). The formula checksums are refreshed by CI after each `v*` tag.
 | `~/.microbridge/config.toml` | Key source, lighting, appearance |
 | `~/.microbridge/daemon.log` | launchd / service logs |
 | `~/.cursor/plugins/local/microbridge` | Bundled Cursor lifecycle integration (only after consent) |
+| `~/Library/LaunchAgents/ai.microbridge.ui.plist` | Login item (only if you enable launch at login) |
+
+## Launch at login
+
+The menu bar app asks once, on first launch, whether to start automatically at
+login, and writes the `ai.microbridge.ui` LaunchAgent if you say yes. Toggle it
+any time in **Settings → General**; it takes effect at your next login. This is
+handled by the app rather than the installer, so Homebrew, DMG, and source
+installs all behave the same way.
 
 ## Troubleshooting
 

apps/microbridge-ui/src-tauri/Cargo.toml

@@ -22,5 +22,6 @@ serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 tokio = { version = "1", features = ["rt-multi-thread", "macros", "net", "io-util", "sync"] }
 mb-protocol = { path = "../../../crates/mb-protocol" }
+tauri-plugin-autostart = "2.5.1"
 
 [workspace]