docs: cut 6.1.0 versions for user_docs, admin_docs, developer_docs, components

Snapshots all four versioned Docusaurus sections at v6.1.0, cut from
master after the version-cutting tooling (#39837), broken-internal-
links fix (#40102), and user_docs rename (#40171) all landed. With
the rename in place, all four sections now produce parallel-named
files at the docs/ root (no more bare `versioned_docs/` outlier).

Versioning behavior: lastVersion stays at current for every section,
so the canonical URLs (/user-docs/..., /admin-docs/...,
/developer-docs/..., /components/...) continue to render content
from master. The current version is consistently labeled "Next"
with an unreleased banner, and 6.1.0 is a historical pin accessible
only via its explicit version segment.

Component playground: previously disabled: true in versions-config.json,
now enabled and versioned.

Snapshot includes:
- All MDX content for the four sections.
- Auto-gen captured fresh: 74 database pages (engine spec metadata),
  ~1,800 API reference files (openapi.json), 59 component pages
  (Storybook stories).
- Data imports frozen at cut time into snapshot-local _versioned_data/
  dirs:
    user_docs_versioned_docs/version-6.1.0/_versioned_data/src/data/databases.json
      (canonical 80-database diagnostics from master, preserved by the
      generator's input-hash cache)
    admin_docs_versioned_docs/version-6.1.0/_versioned_data/data/countries.json
    admin_docs_versioned_docs/version-6.1.0/_versioned_data/static/feature-flags.json
    developer_docs_versioned_docs/version-6.1.0/_versioned_data/static/data/components.json
- Import paths in deeply-nested files rewritten so they still resolve
  from one directory deeper inside the snapshot.
- developer_docs/extensions/overview.md snapshot has the FIXED
  ./mcp.md form (from #40102), so the SPA-nav 404 isn't baked into
  the 6.1.0 version.

Verified via full yarn build: exit 0, no broken links surfaced by
onBrokenLinks: throw.

docs/developer_docs_versioned_docs/version-6.1.0/api/get-a-guest-token.api.mdx

@@ -0,0 +1,66 @@
+---
+id: get-a-guest-token
+title: "Get a guest token"
+description: "Get a guest token"
+sidebar_label: "Get a guest token"
+hide_title: true
+hide_table_of_contents: true
+api: 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
+sidebar_class_name: "post api-method"
+info_path: developer-docs/api/superset
+custom_edit_url: null
+hide_send_button: true
+show_extensions: true
+---
+
+import MethodEndpoint from "@theme/ApiExplorer/MethodEndpoint";
+import ParamsDetails from "@theme/ParamsDetails";
+import RequestSchema from "@theme/RequestSchema";
+import StatusCodes from "@theme/StatusCodes";
+import OperationTabs from "@theme/OperationTabs";
+import TabItem from "@theme/TabItem";
+import Heading from "@theme/Heading";
+import Translate from "@docusaurus/Translate";
+
+<Heading
+  as={"h1"}
+  className={"openapi__heading"}
+  children={"Get a guest token"}
+>
+</Heading>
+
+<MethodEndpoint
+  method={"post"}
+  path={"/api/v1/security/guest_token/"}
+  context={"endpoint"}
+>
+
+</MethodEndpoint>
+
+
+
+Get a guest token
+
+<Heading
+  id={"request"}
+  as={"h2"}
+  className={"openapi-tabs__heading"}
+>
+  <Translate id="theme.openapi.request.title">Request</Translate>
+</Heading>
+
+<ParamsDetails>
+
+</ParamsDetails>
+
+<RequestSchema
+  {...require("./get-a-guest-token.RequestSchema.json")}
+>
+
+</RequestSchema>
+
+<StatusCodes
+  {...require("./get-a-guest-token.StatusCodes.json")}
+>
+
+</StatusCodes>