docs: bring docforge docstrings and wiki to GSDFC standard

- fix GSDFC spec contradictions in __init__ docstring (parenthesized types, fenced-block rule) and sync generated README
- rewrite docstrings across loaders, models, nav, servers, renderers, cli; sync .pyi stubs
- add pydoclint (google style) gate to dev extras and pyproject config
- fix mcp nav resources doc:// -> docs://
- refresh docs/lib and docs/mcp, drop stale docforge/ duplicate group
- update wiki pages and add GSDFC + MCP guides under 05_development

docs/mcp/modules/docforge.servers.mcp_server.json

@@ -2,7 +2,7 @@
   "module": "docforge.servers.mcp_server",
   "content": {
     "path": "docforge.servers.mcp_server",
-    "docstring": "# Summary\n\nMCP server implementation.\n\nThis module defines the `MCPServer` class, which serves pre-generated\ndocumentation bundles through the Model Context Protocol (MCP).",
+    "docstring": "# Summary\n\nMCP server implementation.\n\nThis module defines the `MCPServer` class, which serves pre-generated\ndocumentation bundles through the Model Context Protocol (MCP).\n\n---\n\nNotes:\n    - The served bundle is generated offline by `MCPRenderer`.\n    - Missing resources are reported as structured error dictionaries rather\n      than raising exceptions.\n    - The server exposes read-only resources and a single health-check tool.\n\n---",
     "objects": {
       "annotations": {
         "name": "annotations",
@@ -50,8 +50,8 @@
         "name": "MCPServer",
         "kind": "class",
         "path": "docforge.servers.mcp_server.MCPServer",
-        "signature": "<bound method Class.signature of Class('MCPServer', 19, 134)>",
-        "docstring": "MCP server for serving a pre-generated documentation bundle.\n\nThe server exposes documentation resources and diagnostic tools through\nMCP endpoints backed by JSON files generated by the MCP renderer.",
+        "signature": "<bound method Class.signature of Class('MCPServer', 29, 152)>",
+        "docstring": "MCP server for serving a pre-generated documentation bundle.\n\nThe server exposes documentation resources and diagnostic tools through\nMCP endpoints backed by JSON files generated by the MCP renderer.\n\nAttributes:\n    mcp_root (Path):\n        Directory containing the generated MCP documentation bundle.\n\n    app (FastMCP):\n        Underlying FastMCP application instance that registers resources\n        and tools.",
         "members": {
           "mcp_root": {
             "name": "mcp_root",
@@ -71,7 +71,7 @@
             "name": "run",
             "kind": "function",
             "path": "docforge.servers.mcp_server.MCPServer.run",
-            "signature": "<bound method Function.signature of Function('run', 122, 134)>",
+            "signature": "<bound method Function.signature of Function('run', 140, 152)>",
             "docstring": "Start the MCP server.\n\nArgs:\n    transport (Literal[\"stdio\", \"sse\", \"streamable-http\"]):\n        Transport mechanism used by the MCP server. Supported options\n        include `stdio`, `sse`, and `streamable-http`."
           }
         }