feat(aiturk): add the connect-to-computer screen (QR scan, code, deep link)

Landing now leads with QR / 8-character code pairing; manual login stays as the secondary action. aiturk://pair links open the same screen and ask for confirmation first.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01B8ppceaR5s6cvMnm7uGRnf

app/src/main/java/com/m57/hermescontrol/Navigation.kt

@@ -52,6 +52,7 @@ import com.m57.hermescontrol.data.local.AuthManager
 import com.m57.hermescontrol.data.ws.ConnectionStatus
 import com.m57.hermescontrol.data.ws.HermesWsClient
 import com.m57.hermescontrol.theme.LocalHermesStatusColors
+import com.m57.hermescontrol.ui.aiturkpair.AiturkPairDeepLinkEffect
 import com.m57.hermescontrol.ui.common.DisableDrawerGestures
 import com.m57.hermescontrol.ui.common.DrawerGestureController
 import com.m57.hermescontrol.ui.common.LocalDrawerGestureController
@@ -66,6 +67,7 @@ import com.m57.hermescontrol.ui.settings.SettingsVaultPage
 import com.m57.hermescontrol.ui.settings.SettingsViewModel
 import com.m57.hermescontrol.ui.toolsets.ToolsetDetailScreen
 import kotlinx.coroutines.launch
+import com.m57.hermescontrol.ui.aiturkpair.AiturkPairScreen as AiturkPairScreenContent
 import com.m57.hermescontrol.ui.authlogin.AuthLoginScreen as AuthLoginScreenContent
 import com.m57.hermescontrol.ui.landing.LandingScreen as LandingScreenContent
 
@@ -79,6 +81,9 @@ private fun appEntryProvider(
             onAuthLogin = {
                 NavigationController.navigateTo(AuthLoginScreen)
             },
+            onAiturkPair = {
+                NavigationController.navigateTo(AiturkPairScreen)
+            },
         )
         // Landing doesn't use HermesScaffold — opt out of drawer gestures explicitly (issue #619).
         DisableDrawerGestures()
@@ -96,6 +101,18 @@ private fun appEntryProvider(
         DisableDrawerGestures()
     }
 
+    entry<AiturkPairScreen> {
+        AiturkPairScreenContent(
+            onConnected = {
+                NavigationController.resetTo(ChatScreen)
+            },
+            onBack = {
+                NavigationController.goBack()
+            },
+        )
+        DisableDrawerGestures()
+    }
+
     ScreenRegistry.ALL_SCREENS.forEach { screen ->
         addEntryProvider(clazz = screen.key::class) {
             screen.content(sessionId, openDrawer)
@@ -193,6 +210,7 @@ fun MainNavigation(sessionId: String? = null) {
 
     val backStack = remember(startScreen) { NavBackStack(startScreen) }
     NavigationController.backStack = backStack
+    AiturkPairDeepLinkEffect()
 
     val currentScreen = backStack.lastOrNull() ?: startScreen
     val drawerState = rememberDrawerState(initialValue = DrawerValue.Closed)