chore(ui): add no-console lint ratchet and strip console from prod builds

Introduce a gradual ratchet to remove raw console.* calls from the
dashboard, mirroring the existing no-explicit-any budget.

The no-console eslint rule is set to warn with allow: [warn, error] so
the 486 console.log/debug/info calls are tracked without force-deleting
the legitimate console.error/warn error reporting in catch blocks. The
count is grandfathered via eslint-budgets.json (max 486, target 0) and
eslint-metrics.json, so any newly added console.log fails the budget
check and follow-up PRs grind the max down toward zero.

Independently, next.config strips console output from production builds
via SWC removeConsole (exclude: [error]), gated on NODE_ENV=production so
dev keeps full console output. This gives an immediate prod-hygiene net
regardless of how long the source cleanup takes. Verified against a real
production build: app-code console.log dropped from 675 to 14 in the
bundle (remainder is node_modules, which the transform leaves alone),
console.warn app calls stripped, console.error preserved 906 to 906.

ui/litellm-dashboard/eslint-budgets.json

@@ -1,5 +1,6 @@
 {
   "@typescript-eslint/no-explicit-any": { "max": 2040, "target": 1500 },
+  "no-console": { "max": 486, "target": 0 },
   "complexity": { "max": 140, "target": 80 },
   "max-depth": { "max": 70, "target": 30 }
 }

ui/litellm-dashboard/eslint-metrics.json

@@ -1,5 +1,6 @@
 {
   "@typescript-eslint/no-explicit-any": 1991,
   "complexity": 128,
-  "max-depth": 59
+  "max-depth": 59,
+  "no-console": 486
 }

ui/litellm-dashboard/eslint.config.mjs

@@ -17,6 +17,7 @@ const eslintConfig = [
     rules: {
       "unused-imports/no-unused-imports": "error",
       "@typescript-eslint/no-explicit-any": "warn",
+      "no-console": ["warn", { allow: ["warn", "error"] }],
       "@typescript-eslint/no-unused-vars": "off",
       "@typescript-eslint/no-unused-expressions": "off",
       "@typescript-eslint/ban-ts-comment": "off",

ui/litellm-dashboard/next.config.mjs

@@ -7,6 +7,9 @@ const __dirname = path.dirname(__filename);
 
 const nextConfig = {
   output: "export",
+  compiler: {
+    removeConsole: process.env.NODE_ENV === "production" ? { exclude: ["error"] } : false,
+  },
   // Required with output: "export" — default image optimizer runs only in server mode.
   // See https://nextjs.org/docs/messages/export-image-api
   images: {