chore(claude): bump mimicked CLI to 2.1.92 and extend anthropic-beta list

Align Claude Code mimicry constants with the latest real CLI traffic
(see Parrot's src/transform/cc_mimicry.py). Anthropic now uses the full
set of anthropic-beta tokens to decide whether a request counts as
"official Claude Code"; requests missing tokens that real CLI ships
today are demoted to third-party usage:

  Third-party apps now draw from your extra usage, not your plan limits.

Changes:
  - claude/constants.go: add new beta tokens (prompt-caching-scope,
    effort, redact-thinking, context-management, extended-cache-ttl) and
    expose FullClaudeCodeMimicryBetas() for the OAuth mimicry path.
  - claude/constants.go: bump default User-Agent to claude-cli/2.1.92.
  - identity_service.go: bump defaultFingerprint User-Agent accordingly.

No behavioral change for clients that already send a newer UA (fingerprint
merge still prefers the incoming value).

backend/internal/service/identity_service.go

@@ -26,7 +26,7 @@ var (
 
 // 默认指纹值（当客户端未提供时使用）
 var defaultFingerprint = Fingerprint{
-	UserAgent:               "claude-cli/2.1.22 (external, cli)",
+	UserAgent:               "claude-cli/2.1.92 (external, cli)",
 	StainlessLang:           "js",
 	StainlessPackageVersion: "0.70.0",
 	StainlessOS:             "Linux",