feat(ai): unify reply center and refresh keyboard AI features

- Merge invitation, task, blessing, clarification, and empathy actions
  into a single Reply flow, with three fixed, clearly labeled stance
  choices whenever user intent must not be guessed.
- Refine clipboard semantic routing with bilingual schedule,
  confirmation, and follow-up models, conservative language thresholds,
  and explicit-assignment guard for complaint-only text.
- Persist Apple account refresh state, harden session recovery, and
  surface durable account diagnostics across keyboard and app.
- Derive personal-style prompts through two-stage corpus evidence and
  apply real low-confidence ASR tendencies instead of neutral templates.
- Localize the new reply center, clipboard semantics, and personal-style
  surfaces in both English and Simplified Chinese.

OSGKeyboardShared/Models/AppGroupConfiguration.swift

@@ -213,7 +213,7 @@ public struct AppGroupConfiguration: Sendable, Equatable {
     ) -> LLMClient {
         if credentialSource == .managed || requestPurpose == .oobe {
             return ManagedLLMClient(
-                capability: .polish,
+                capability: .resolve(taskKind: taskKind),
                 taskKind: taskKind,
                 requestPurpose: requestPurpose,
                 oobeFeature: oobeFeature,