feat: consolidated Gitea API client and pi extension

- Pure fetch-based API client (src/) with zero external dependencies
- Pi extension adapter (pi-extension/) registering 17 tools
- Standalone CLI (cli.ts) replacing gitea-scripts/gitea.js
- Token auth everywhere (no HMAC secrets)
- SKILL.md for agent auto-discovery
- TOOL.md with full parameter reference

Consolidates pi-bot/extensions/pi-gitea and clawbot/gitea-scripts
into a single shared package.

package.json

@@ -0,0 +1,16 @@
+{
+  "name": "gitea",
+  "version": "1.0.0",
+  "description": "Gitea API client and pi extension for git.dominat.us",
+  "type": "module",
+  "exports": {
+    ".": "./src/index.ts",
+    "./cli": "./cli.ts"
+  },
+  "bin": {
+    "gitea": "./cli.ts"
+  },
+  "scripts": {
+    "cli": "npx tsx cli.ts"
+  }
+}