feat: refine OAuth proxy controls and quota UI (#433)

* feat: refine oauth management proxy controls

* fix: preserve oauth refresh state and tighten oauth rate limiting

* fix: satisfy codeql oauth rate limiting

* fix: address oauth review comments

* fix: move oauth sensitive limits into prehandlers

* fix: cap oauth quota refresh batch size

package-lock.json

@@ -29,6 +29,7 @@
         "node-cron": "^4.2.1",
         "nodemailer": "^8.0.4",
         "pg": "^8.16.3",
+        "rate-limiter-flexible": "^11.0.0",
         "socks": "^2.8.7",
         "undici": "^6.24.1",
         "ws": "^8.20.0",
@@ -12600,6 +12601,12 @@
         "url": "https://github.com/sponsors/sindresorhus"
       }
     },
+    "node_modules/rate-limiter-flexible": {
+      "version": "11.0.0",
+      "resolved": "https://registry.npmjs.org/rate-limiter-flexible/-/rate-limiter-flexible-11.0.0.tgz",
+      "integrity": "sha512-UhN3xVeU6Az3y6hAuxMUwFsKcKD1HffhMGK0MknbSxH9vkwslS/p19ovCvJqIVT97pE778nKu2sUgYAcxj4dmQ==",
+      "license": "ISC"
+    },
     "node_modules/rc": {
       "version": "1.2.8",
       "resolved": "https://registry.npmjs.org/rc/-/rc-1.2.8.tgz",