feat: add the aegis-gitea-mcp setup command

Verifies the Gitea instance, token and scopes, registers or reuses the aegis-gitea-mcp OAuth app, generates missing secrets and writes a 0600 env file from the template. Prints client configs and deployment snippets without any secret value.

src/aegis_gitea_mcp/cli.py

@@ -10,7 +10,7 @@ import argparse
 import sys
 from collections.abc import Sequence
 
-from aegis_gitea_mcp import __version__
+from aegis_gitea_mcp import __version__, setup_cmd
 
 
 def build_parser() -> argparse.ArgumentParser:
@@ -29,7 +29,8 @@ def build_parser() -> argparse.ArgumentParser:
         help="transport to serve (default: MCP_TRANSPORT, else stdio)",
     )
 
-    subparsers.add_parser("setup", help="interactive setup against a Gitea instance")
+    setup = subparsers.add_parser("setup", help="verify a Gitea instance and write the env file")
+    setup_cmd.add_arguments(setup)
     subparsers.add_parser("version", help="print the version and exit")
     return parser
 
@@ -48,6 +49,8 @@ def main(argv: Sequence[str] | None = None) -> int:
     if command == "version":
         print(__version__)
         return 0
+    if command == "setup":
+        return setup_cmd.run_setup(args)
     return _not_implemented(command)