feat(apisix): add Cloudron package

- Implements Apache APISIX packaging for Cloudron platform.
- Includes Dockerfile, CloudronManifest.json, and start.sh.
- Configured to use Cloudron's etcd addon.

🤖 Generated with Gemini CLI
Co-Authored-By: Gemini <noreply@google.com>

CloudronPackages/APISIX/apisix-source/t/certs/server_sign.key

@@ -0,0 +1,5 @@
+-----BEGIN PRIVATE KEY-----
+MIGHAgEAMBMGByqGSM49AgEGCCqBHM9VAYItBG0wawIBAQQgMjFhLon1CAQdzFWt
+0Mre0juQiCDbXOY8ljWqSzQN9EehRANCAAShkoshwOaCHk9d7jS98sSvrfayoQDB
+08w00ANNWcpR2C5+l3ZLFroGbD+rU8f9vtezZkZGhx98M7X+nIg91mZw
+-----END PRIVATE KEY-----