feat(settings): runtime log level + free provider enable/disable

- Add LOG_LEVEL env + runtime setLogLevel (dashboard Settings → Logging),
  applied immediately, persisted across restarts; WARN/ERROR quiet production
  INFO lines (▶ POST / 📊 DONE / [COMBO] / [CHAT])
- Allow toggling free/noAuth providers (gemini-cli, kilo, etc.) off via
  providerStrategies.enabled from Providers page and provider detail page
- auth.js: honor disabled override before noAuth/connection branches
- CompatibleModelsSection: parallel model testing

src/shared/services/initializeApp.js

@@ -3,6 +3,7 @@ import { fileURLToPath } from "url";
 import { dirname, join } from "path";
 import { existsSync } from "fs";
 import { cleanupProviderConnections, getSettings, updateSettings, getApiKeys } from "@/lib/localDb";
+import { setLogLevel } from "@/sse/utils/logger";
 import {
   enableTunnel, enableTailscale,
   isTunnelManuallyDisabled, isTunnelReconnecting, isTailscaleReconnecting,
@@ -83,6 +84,14 @@ async function runHeavyStartup() {
   await cleanupProviderConnections();
   const settings = await getSettings();
 
+  // Apply persisted log level (dashboard Settings → Logging) so production
+  // logs stay quiet (ERROR only) even after a restart.
+  try {
+    setLogLevel(settings.logLevel);
+  } catch (e) {
+    console.warn("[InitApp] setLogLevel failed:", e.message);
+  }
+
   // Auto-resume tunnel (once per process)
   if (settings.tunnelEnabled && !g.tunnelAutoResumed) {
     g.tunnelAutoResumed = true;