fix: vendor per-kind sites in the hub; drop stale blog docs

- collect.py: when a kind points at the shared site root, copy only the
  per-kind subdir (site/lib -> <repo>/lib) instead of the whole site, so
  stray single-site build output never leaks into the hub
- Purge stale collected artifacts (404.html, assets/, search/, sitemaps,
  objects.inv, duplicate mcp/) from every repo dir, matching the cleaned
  source site/ roots
- Refresh collected output from source repos, incl. the khata-app app
- Remove the vendored Blog API docs (config.yml entry + blog/) and its card

openapi-first/mcp/modules/openapi_first.templates.model_app.models.json

@@ -1,62 +0,0 @@
-{
-  "module": "openapi_first.templates.model_app.models",
-  "content": {
-    "path": "openapi_first.templates.model_app.models",
-    "docstring": "Pydantic domain models for the CRUD example.\n\nThis module defines Pydantic models that represent the domain entities\nused by the service. These models are referenced by the OpenAPI\nspecification for request and response schemas.\n\nThe models are declarative and framework-agnostic. They contain no\npersistence logic, validation beyond type constraints, or business\nbehavior.\n\nThis module is not part of the ``openapi_first`` library API surface.\nIt exists solely to support the example application template.",
-    "objects": {
-      "BaseModel": {
-        "name": "BaseModel",
-        "kind": "alias",
-        "path": "openapi_first.templates.model_app.models.BaseModel",
-        "signature": "<bound method Alias.signature of Alias('BaseModel', 'pydantic.BaseModel')>",
-        "docstring": null
-      },
-      "ItemBase": {
-        "name": "ItemBase",
-        "kind": "class",
-        "path": "openapi_first.templates.model_app.models.ItemBase",
-        "signature": "<bound method Class.signature of Class('ItemBase', 19, 27)>",
-        "docstring": "Base domain model for an item.\n\nDefines fields common to all item representations.",
-        "members": {
-          "name": {
-            "name": "name",
-            "kind": "attribute",
-            "path": "openapi_first.templates.model_app.models.ItemBase.name",
-            "signature": null,
-            "docstring": null
-          },
-          "price": {
-            "name": "price",
-            "kind": "attribute",
-            "path": "openapi_first.templates.model_app.models.ItemBase.price",
-            "signature": null,
-            "docstring": null
-          }
-        }
-      },
-      "ItemCreate": {
-        "name": "ItemCreate",
-        "kind": "class",
-        "path": "openapi_first.templates.model_app.models.ItemCreate",
-        "signature": "<bound method Class.signature of Class('ItemCreate', 30, 39)>",
-        "docstring": "Domain model for item creation requests.\n\nThis model is used for request bodies when creating new items.\nIt intentionally excludes the ``id`` field, which is assigned\nby the service."
-      },
-      "Item": {
-        "name": "Item",
-        "kind": "class",
-        "path": "openapi_first.templates.model_app.models.Item",
-        "signature": "<bound method Class.signature of Class('Item', 42, 50)>",
-        "docstring": "Domain model for a persisted item.\n\nThis model represents the full item state returned in responses,\nincluding the server-assigned identifier.",
-        "members": {
-          "id": {
-            "name": "id",
-            "kind": "attribute",
-            "path": "openapi_first.templates.model_app.models.Item.id",
-            "signature": null,
-            "docstring": null
-          }
-        }
-      }
-    }
-  }
-}