Merge remote-tracking branch 'origin/master' into gitea/feature/end

Resolved conflicts taking origin/master (v0.5.55) as canonical, with local
features re-applied:
- runtime log level (LOG_LEVEL env + dashboard Settings → Logging, applied
  immediately and persisted across restarts)
- free/noAuth provider enable/disable toggle via providerStrategies.enabled
- parallel model testing (Test All Models / Test Selected Keys)

i18n/README.zh-CN.md

@@ -42,25 +42,26 @@
 
 ```
 ┌─────────────┐
-│  Your CLI   │  (Claude Code, Codex, Gemini CLI, OpenClaw, Cursor, Cline...)
+│  Your CLI   │  (Claude Code, Codex, OpenClaw, Cursor, Cline, Antigravity...)
 │   Tool      │
 └──────┬──────┘
-       │ http://localhost:201281
+       │ http://localhost:20128/v1
        ↓
-┌─────────────────────────────────────────┐
-│           9Router (Smart Router)        │
-│  • Format translation (OpenAI ↔ Claude) │
-│  • Quota tracking                       │
-│  • Auto token refresh                   │
-└──────┬──────────────────────────────────┘
+┌─────────────────────────────────────────────┐
+│           9Router (Smart Router)            │
+│  • RTK Token Saver (节省 20-40% Token)      │
+│  • 格式转换 (OpenAI ↔ Claude)               │
+│  • 配额追踪 (Quota tracking)                │
+│  • 自动刷新 OAuth Token                     │
+└──────┬──────────────────────────────────────┘
        │
-       ├─→ [Tier 1: SUBSCRIPTION] Claude Code, Codex, Gemini CLI
-       │   ↓ quota exhausted
-       ├─→ [Tier 2: CHEAP] GLM ($0.6/1M), MiniMax ($0.2/1M)
-       │   ↓ budget limit
-       └─→ [Tier 3: FREE] iFlow, Qwen, Kiro (unlimited)
+       ├─→ [Tier 1: 订阅] Claude Code, Codex, GitHub Copilot
+       │   ↓ 配额用尽
+       ├─→ [Tier 2: 低价] GLM ($0.6/1M), MiniMax ($0.2/1M)
+       │   ↓ 触及预算上限
+       └─→ [Tier 3: 免费] Kiro AI, OpenCode Free, Vertex AI ($300 credits)
 
-Result: Never stop coding, minimal cost
+结果：永不停歇的编程体验，最低成本 + 通过 RTK 节省 20-40% Token
 ```
 
 ---