Merge origin/master (v0.5.81) into gitea/new_feature

Resolve conflicts:
- streamingHandler.js: merge buildStreamErrorBytes onAbortTerminal + local shouldPersistRequestDetail & streamStatusForContent
- capabilities.js: preserve server-injected user-asserted caps and models.dev catalog lookup; wire CommandCode /alpha/generate caps inside resolve()
- commandcode.js (services/usage): adopt upstream whoami + billing credits/subscriptions with 5h/weekly rate windows and plan caps
- openai-to-commandcode.js: merge toNativeImageBlock (data-URI & http(s) support) and assistant reasoning_content preservation
- commandcode-to-openai.js: adopt upstream mid-stream error throw for clean retry and abortion
- tests: sync commandcode test suite and exclude .next from vitest config

package.json

@@ -1,6 +1,6 @@
 {
   "name": "9router-app",
-  "version": "0.5.75",
+  "version": "0.5.81",
   "description": "9Router web dashboard",
   "private": true,
   "scripts": {