feat(keyboard): improve typing, voice flow, and polish reliability

Reduce extension memory pressure and delivery races while adding richer candidates, tactile feedback, and safer two-level creative polishing.

OSGKeyboardTests/ConfigurationStoreTests.swift

@@ -6,6 +6,7 @@
 
 import XCTest
 @testable import OSGKeyboardShared
+@testable import OSGKeyboardHostSupport
 
 final class ConfigurationStoreTests: XCTestCase {
     private var suiteName: String!
@@ -36,6 +37,12 @@ final class ConfigurationStoreTests: XCTestCase {
         )
     }
 
+    /// Unsigned test hosts may lack the App Group container. Bare
+    /// `AppGroupStore()` must not `fatalError` while XCTest is loaded.
+    func testBareAppGroupStoreDoesNotTrapUnderXCTest() {
+        _ = AppGroupStore()
+    }
+
     func testASRFactoryAcceptsConfigurationStore() {
         store.setEngineMode("local")
         let service = ASRServiceFactory.make(store: store as any ConfigurationStore)