feat(ops-bridge): add HTTP/SSE MCP transport for remote Claude Code sessions

server.py: MCP_TRANSPORT and MCP_PORT env vars select transport at startup
  (default: stdio — no behaviour change for local use)
Makefile: `make mcp-http` starts SSE server on 127.0.0.1:8001

Remote registration (one-liner on COULOMBCORE after tunnel is up):
  claude mcp add-json -s user state-hub \
    '{"type":"sse","url":"http://127.0.0.1:18001/sse"}'

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

mcp_server/server.py

@@ -1421,4 +1421,9 @@ def update_repo_goal(
 # ---------------------------------------------------------------------------
 
 if __name__ == "__main__":
-    mcp.run(transport="stdio")
+    transport = os.environ.get("MCP_TRANSPORT", "stdio")
+    if transport == "stdio":
+        mcp.run(transport="stdio")
+    else:
+        port = int(os.environ.get("MCP_PORT", "8001"))
+        mcp.run(transport=transport, host="127.0.0.1", port=port)