feat: Add OAuth2 server and client implementation with PKCE support

- Implemented OAuth2 server with client registration, authorization, and token endpoints.
- Created HTML templates for client authorization, client creation, and client editing.
- Developed an OAuth2 client application using Hono.js and Bun, supporting authorization code grant flow.
- Integrated PKCE (Proof Key for Code Exchange) for enhanced security during authorization.
- Added session management using cookies for user authentication.
- Included detailed README documentation for setup and usage instructions.

oauth2-attacker/package.json

@@ -0,0 +1,19 @@
+{
+  "name": "oauth2-attacker",
+  "module": "index.ts",
+  "type": "module",
+  "private": true,
+  "scripts": {
+    "dev": "bun run --hot index.ts",
+    "start": "bun run index.ts"
+  },
+  "devDependencies": {
+    "@types/bun": "latest"
+  },
+  "peerDependencies": {
+    "typescript": "^5"
+  },
+  "dependencies": {
+    "hono": "^4.8.4"
+  }
+}