refactor(flow): remove Live Activity and keep-alive mode picker

Keep voice sessions on silent low-profile PiP only, and fix custom polish style editor presentation via sheet(item:).

OSGKeyboardTests/AppGroupConfigurationTests.swift

@@ -34,22 +34,9 @@ final class AppGroupConfigurationTests: XCTestCase {
         XCTAssertEqual(config.polishIntensity, .light)
         XCTAssertTrue(config.personalDictionary.entries.isEmpty)
         XCTAssertTrue(config.flowSkipAppSwitch)
-        XCTAssertEqual(config.flowKeepAliveMode, .pictureInPicture)
         XCTAssertEqual(config.flowInactivityDuration, .fiveMinutes)
     }
 
-    func testLoadPreservesStoredLiveActivityKeepAliveMode() {
-        let defaults = makeDefaults()
-        defaults.set(
-            FlowKeepAliveMode.liveActivity.rawValue,
-            forKey: AppGroupConfiguration.Keys.flowKeepAliveMode
-        )
-
-        let config = AppGroupConfiguration.load(fromAvailable: defaults)
-
-        XCTAssertEqual(config.flowKeepAliveMode, .liveActivity)
-    }
-
     func testSaveAndLoadRoundTrip() {
         let defaults = makeDefaults()
         var config = AppGroupConfiguration.load(fromAvailable: defaults)
@@ -73,7 +60,6 @@ final class AppGroupConfigurationTests: XCTestCase {
         config.keyboardHapticIntensity = .strong
         config.polishIntensity = .heavy
         config.flowSkipAppSwitch = false
-        config.flowKeepAliveMode = .pictureInPicture
         // Use a non-default value so the round-trip actually proves persistence.
         config.flowInactivityDuration = .threeHours
         config.save(to: defaults)
@@ -98,7 +84,6 @@ final class AppGroupConfigurationTests: XCTestCase {
         XCTAssertEqual(loaded.keyboardHapticIntensity, .strong)
         XCTAssertEqual(loaded.polishIntensity, .heavy)
         XCTAssertFalse(loaded.flowSkipAppSwitch)
-        XCTAssertEqual(loaded.flowKeepAliveMode, .pictureInPicture)
         XCTAssertEqual(loaded.flowInactivityDuration, .threeHours)
     }