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

Snapshots all four versioned Docusaurus sections at v6.1.0. Built on
top of the version-cutting tooling work in chore/docs-cut-6.1.0-versions
so the snapshot benefits from:

- Auto-gen refresh before snapshotting (database pages from engine
  spec metadata, API reference from openapi.json, component pages
  from Storybook stories) — captured at the SHA we cut from rather
  than whatever happened to be on disk.
- Data-import freeze: country list, feature flag table, database
  diagnostics, and component metadata are copied into snapshot-local
  `_versioned_data/` dirs so the historical version doesn't silently
  mutate when the source files change.
- Depth-aware import-path rewriter that handles deeply-nested
  component MDX files referencing `../../../src/` from the snapshot.

Versioning behavior: `lastVersion` stays at `current` for every
section, so the canonical URLs (`/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. The plugin block in docusaurus.config.ts
was already gated only by the `disabled` flag, so no other code
changes were needed to bring it back online.

The frozen `databases.json` in the snapshot is the canonical 80-database
artifact from the latest committed state in master (preserved by the
generator's input-hash cache), not a fallback regenerated from a
local Flask environment.

docs/developer_docs_versioned_docs/version-6.1.0/api/get-all-available-domains.api.mdx

@@ -0,0 +1,58 @@
+---
+id: get-all-available-domains
+title: "Get all available domains"
+description: "Get all available domains"
+sidebar_label: "Get all available domains"
+hide_title: true
+hide_table_of_contents: true
+api: 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
+sidebar_class_name: "get 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 all available domains"}
+>
+</Heading>
+
+<MethodEndpoint
+  method={"get"}
+  path={"/api/v1/available_domains/"}
+  context={"endpoint"}
+>
+
+</MethodEndpoint>
+
+
+
+Get all available domains
+
+<ParamsDetails>
+
+</ParamsDetails>
+
+<RequestSchema
+  {...require("./get-all-available-domains.RequestSchema.json")}
+>
+
+</RequestSchema>
+
+<StatusCodes
+  {...require("./get-all-available-domains.StatusCodes.json")}
+>
+
+</StatusCodes>