fix(gamepad/android): batched HAT, rumble-duration floor, bind eviction, held exit chord (G4/G9/G18/G24)

Four Android gamepad fixes bringing the client to parity with SDL/Apple:

G4 — HAT batched history. Android batches joystick ACTION_MOVEs, so a
rapid d-pad tap (press+release within one batch) lived only in the event's
historical samples; onMotion read just the final getAxisValue and missed
it. Feed every historical HAT sample through the transition logic (new
`applyHat`) before the current one. Sticks/triggers stay latest-wins.

G9 — floor the rumble one-shot duration. A v2 lease can carry ttl_ms==0
with a nonzero amplitude (past the (0,0) stop guard); createOneShot throws
on a non-positive duration, and on the VibratorManager path the effect is
built outside the vibrate() runCatching, so the throw would kill the whole
rumble poll thread. `durationMs.coerceAtLeast(1)`.

G18 — evict feedback binds on disconnect. Rumble/light bindings were
cached by device id and freed only at session stop, so a controller
unplugged mid-session leaked its open LightsSession. Add
GamepadFeedback.onDeviceRemoved(deviceId) (closes the session, cancels
rumble), invoked from GamepadRouter's slot-close via a new onSlotClosed
callback wired in StreamScreen. The bind maps are now guarded by a lock
(the poll threads write them; eviction runs on the main thread).

G24 — held exit chord + releases. The emergency-exit chord (Select+Start+
L1+R1) quit the stream the instant it completed — an accidental brush
killed the session, and the four held buttons were never released
host-side. Now completing the chord ARMS a 1.5 s hold timer (matching
DISCONNECT_HOLD on SDL/Apple); onExitChord fires only if still held at
expiry, after releasing the held buttons + zeroing the axes on the
triggering pad(s). onButton no longer returns the exit bool (async now);
MainActivity + StreamScreen updated.

G25 (Android half): no change — Android's stick/trigger `.toInt()` already
truncates, the chosen cross-client convention. G23 (rich-input plane) stays
deferred to its own doc.

Verified on this Mac: :kit + :app compileDebugKotlin clean; kit lint
unchanged at its pre-existing baseline. On-glass on a real phone + pad
still owed (per the Android-regressions-only-show-on-hardware history):
watch batched d-pad taps, the 1.5 s exit hold, and a mid-session unplug.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

clients/android/app/src/main/kotlin/io/unom/punktfunk/MainActivity.kt

@@ -127,12 +127,12 @@ class MainActivity : ComponentActivity() {
             if (event.isFromSource(InputDevice.SOURCE_GAMEPAD)) {
                 val bit = Gamepad.buttonBit(event.keyCode)
                 if (bit != 0) {
-                    // The router forwards the bit on this device's own wire pad index, tracks held
-                    // state per pad, and reports when the emergency-exit chord (Select + Start + L1 +
-                    // R1) completed on any one pad (a couch user has no keyboard/Back).
-                    if (gamepadRouter?.onButton(event, bit) == true) {
-                        requestStreamExit?.let { exit -> window.decorView.post { exit() } }
-                    }
+                    // The router forwards the bit on this device's own wire pad index and tracks held
+                    // state per pad. The emergency-exit chord (Select + Start + L1 + R1) is handled
+                    // inside the router: holding it for ~1.5 s fires router.onExitChord (wired in
+                    // StreamScreen), so a couch user with no keyboard/Back can still leave — but an
+                    // accidental brush of the four buttons no longer quits instantly.
+                    gamepadRouter?.onButton(event, bit)
                     return true // consumed
                 }
             }

clients/android/app/src/main/kotlin/io/unom/punktfunk/StreamScreen.kt

@@ -180,13 +180,19 @@ fun StreamScreen(handle: Long, micEnabled: Boolean, onDisconnect: () -> Unit) {
         val router = GamepadRouter(context, handle, initialSettings.gamepad)
         activity?.gamepadRouter = router
         // Select+Start+L1+R1 chord leaves the stream — a deliberate quit (signal it so the host skips
-        // the keep-alive linger), unlike a host-ended / backgrounded drop.
+        // the keep-alive linger), unlike a host-ended / backgrounded drop. The router debounces it
+        // (must be held ~1.5 s) and fires onExitChord on its main-thread timer, so leave the stream
+        // the same way the Back gesture does.
         activity?.requestStreamExit = { NativeBridge.nativeDisconnectQuit(handle); onDisconnect() }
+        router.onExitChord = { activity?.requestStreamExit?.invoke() }
         activity?.setConsoleHighRefreshRate(false) // let the decoder's setFrameRate pick the panel rate
         // Host→client feedback (rumble + DualSense lightbar/LEDs), routed to each controller by pad
         // index via the router; poll threads stopped + joined before the router is released and the
         // session closed.
         val feedback = GamepadFeedback(handle, router).also { it.start() }
+        // Free a disconnected controller's rumble/lights bindings promptly (else the open lights
+        // session leaks until the session ends). The router owns hot-plug; the feedback owns the binds.
+        router.onSlotClosed = feedback::onDeviceRemoved
         onDispose {
             closed.set(true) // from here the handle gets freed; surfaceDestroyed must not touch it
             feedback.stop() // stop + join the poll threads BEFORE the router is released / handle freed