feat(git-ops): add GitHub provider with auto-detection

Implements GitHub API provider following the same pattern as Gitea:
- Full PR operations (create, get, list, merge, update, close)
- Branch operations via API
- Comment and label management
- Reviewer request support
- Rate limit error handling

Server enhancements:
- Auto-detect provider from repository URL (github.com vs custom Gitea)
- Initialize GitHub provider when token is configured
- Health check includes both provider statuses
- Token selection based on repo URL for clone/push operations

Refs: #110

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

mcp-servers/git-ops/server.py

@@ -22,7 +22,7 @@ from config import Settings, get_settings
 from exceptions import ErrorCode, GitOpsError
 from git_wrapper import GitWrapper
 from models import MergeStrategy, PRState
-from providers import GiteaProvider
+from providers import BaseProvider, GiteaProvider, GitHubProvider
 from workspace import WorkspaceManager
 
 # Input validation patterns
@@ -77,25 +77,57 @@ logger = logging.getLogger(__name__)
 _settings: Settings | None = None
 _workspace_manager: WorkspaceManager | None = None
 _gitea_provider: GiteaProvider | None = None
+_github_provider: GitHubProvider | None = None
 
 
-def _get_provider_for_url(repo_url: str) -> GiteaProvider | None:
+def _get_provider_for_url(repo_url: str) -> BaseProvider | None:
     """Get the appropriate provider for a repository URL."""
     if not _settings:
         return None
 
+    # Normalize URL for matching
+    url_lower = repo_url.lower()
+
+    # Check for GitHub URLs
+    if "github.com" in url_lower or (
+        _settings.github_api_url
+        and _settings.github_api_url != "https://api.github.com"
+        and _settings.github_api_url.replace("https://", "").replace("/api/v3", "") in url_lower
+    ):
+        return _github_provider
+
     # Check if it's a Gitea URL
-    if _settings.gitea_base_url and _settings.gitea_base_url in repo_url:
+    if _settings.gitea_base_url and _settings.gitea_base_url.lower() in url_lower:
         return _gitea_provider
 
-    # Default to Gitea for now
+    # Default: try to detect from URL pattern
+    # If URL contains 'github' anywhere, use GitHub
+    if "github" in url_lower:
+        return _github_provider
+
+    # Default to Gitea for self-hosted instances
     return _gitea_provider
 
 
+def _get_auth_token_for_url(repo_url: str) -> str | None:
+    """Get the appropriate auth token for a repository URL."""
+    if not _settings:
+        return None
+
+    url_lower = repo_url.lower()
+
+    # GitHub token
+    if "github.com" in url_lower or "github" in url_lower:
+        return _settings.github_token if _settings.github_token else None
+
+    # Gitea token (default)
+    return _settings.gitea_token if _settings.gitea_token else None
+
+
 @asynccontextmanager
 async def lifespan(_app: FastAPI) -> AsyncIterator[None]:
     """Application lifespan handler."""
-    global _settings, _workspace_manager, _gitea_provider
+    global _settings, _workspace_manager, _gitea_provider, _github_provider
 
     logger.info("Starting Git Operations MCP Server...")
 
@@ -114,6 +146,13 @@ async def lifespan(_app: FastAPI) -> AsyncIterator[None]:
         )
         logger.info(f"Gitea provider initialized: {_settings.gitea_base_url}")
 
+    if _settings.github_token:
+        _github_provider = GitHubProvider(
+            token=_settings.github_token,
+            settings=_settings,
+        )
+        logger.info("GitHub provider initialized")
+
     logger.info("Git Operations MCP Server started successfully")
 
     yield
@@ -124,6 +163,9 @@ async def lifespan(_app: FastAPI) -> AsyncIterator[None]:
     if _gitea_provider:
         await _gitea_provider.close()
 
+    if _github_provider:
+        await _github_provider.close()
+
     logger.info("Git Operations MCP Server shut down")
 
 
@@ -167,6 +209,21 @@ async def health_check() -> dict[str, Any]:
     else:
         status["dependencies"]["gitea"] = "not configured"
 
+    # Check GitHub connectivity
+    if _github_provider:
+        try:
+            if await _github_provider.is_connected():
+                user = await _github_provider.get_authenticated_user()
+                status["dependencies"]["github"] = f"connected as {user}"
+            else:
+                status["dependencies"]["github"] = "not connected"
+                is_degraded = True
+        except Exception as e:
+            status["dependencies"]["github"] = f"error: {e}"
+            is_degraded = True
+    else:
+        status["dependencies"]["github"] = "not configured"
+
     # Check workspace directory
     if _workspace_manager:
         try:
@@ -442,10 +499,8 @@ async def clone_repository(
         # Create workspace
         workspace = await _workspace_manager.create_workspace(project_id, repo_url)  # type: ignore[union-attr]
 
-        # Get auth token from provider
-        auth_token = None
-        if _settings and _settings.gitea_token:
-            auth_token = _settings.gitea_token
+        # Get auth token appropriate for the repository URL
+        auth_token = _get_auth_token_for_url(repo_url)
 
         # Clone repository
         git = GitWrapper(workspace.path, _settings)
@@ -715,10 +770,8 @@ async def push(
         if not workspace:
             return {"success": False, "error": f"Workspace not found for project: {project_id}", "code": ErrorCode.WORKSPACE_NOT_FOUND.value}
 
-        # Get auth token
-        auth_token = None
-        if _settings and _settings.gitea_token:
-            auth_token = _settings.gitea_token
+        # Get auth token appropriate for the repository URL
+        auth_token = _get_auth_token_for_url(workspace.repo_url or "")
 
         git = GitWrapper(workspace.path, _settings)
         result = await git.push(