Fix MCP Registry image tag: latest → main

CI pushes :main but server.json referenced :latest, which is a stale
image with a different digest. Align with CI output.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: rodion-m

server.json

@@ -33,7 +33,7 @@
   "packages": [
     {
       "registryType": "oci",
-      "identifier": "ghcr.io/codealive-ai/codealive-mcp:latest",
+      "identifier": "ghcr.io/codealive-ai/codealive-mcp:main",
       "runtimeHint": "docker",
       "transport": {
         "type": "stdio"