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_enc.key

@@ -0,0 +1,5 @@
+-----BEGIN PRIVATE KEY-----
+MIGHAgEAMBMGByqGSM49AgEGCCqBHM9VAYItBG0wawIBAQQgPJQ040ba9lVszMF0
+7S7pzqdxyIMc2fXKr6EsU0vRk2ahRANCAAQP4xCsutn09sybP/jgpvvdBzsWUyzu
+7TfhciaMlEQECfUrNnuOpxh8KJX9u6Ga7WwuExecHr2YRG1/W0BpdyAh
+-----END PRIVATE KEY-----