fix: keyboard stability, host-only analytics, and auto-reply dedupe

- record analytics/usage only in the host app; the extension no longer opens the
  SQLite queues, so hiding the keyboard cannot hold WAL locks (0xdead10cc)
- sync clipboard history writes across processes so deletes made on one side
  are not reverted by the other
- guard memory-relief reentrancy on controller and telemetry sides to break
  the recursive crash loop
- resolve credentials off the main thread and migrate legacy keys once per
  install, so Keychain reads cannot be caught in the suspend window
- gate Volcengine ASR ping completion to once (SIGTRAP on double resume)
- treat same-text captures as the same logical copy and dedupe auto actions
  by content fingerprint within 30s, stopping Universal Clipboard storms
- realign version line to 2.1.0 (build 110)

OSGKeyboardShared/Services/ClipboardHistoryPolicy.swift

@@ -3,6 +3,7 @@
 //
 // Pure rules for accepting clipboard text and simple English/whitespace tokens.
 
+import CryptoKit
 import Foundation
 
 public enum ClipboardHistoryPolicy: Sendable {
@@ -298,4 +299,20 @@ public enum ClipboardHistoryPolicy: Sendable {
     ) -> Bool {
         now.timeIntervalSince(entry.createdAt) <= aiHintEligibilitySeconds
     }
+
+    /// Stable content fingerprint for deduping auto triggers across pasteboard
+    /// generations. SHA-256 because `String.hashValue` is per-process randomized.
+    public static func contentFingerprint(for text: String) -> String {
+        SHA256.hash(data: Data(text.utf8))
+            .map { String(format: "%02x", $0) }
+            .joined()
+    }
+
+    /// Whether an action fired at `firedAt` still suppresses an identical repeat
+    /// at `now`. Universal Clipboard re-announces one copy under several
+    /// changeCounts within seconds; a deliberate re-copy after the window may
+    /// fire again.
+    public static func isRepeatSuppressed(firedAt: Date, now: Date = Date()) -> Bool {
+        now.timeIntervalSince(firedAt) <= aiHintEligibilitySeconds
+    }
 }