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

- Snapshot all four versioned docs sections at v6.1.0; master continues to
  serve as "Next" (lastVersion: current, banner: unreleased) so editing
  master keeps updating the canonical URLs
- Enable the previously-disabled components plugin and version it
- Rename stale "developer_portal" references to "developer_docs" across
  package.json scripts, manage-versions.mjs, theme files (DocVersionBadge,
  DocVersionBanner), DOCS_CLAUDE.md, and README.md (URL backward-compat
  redirect /developer_portal/* preserved)
- Add admin_docs version scripts; drop dead "tutorials" plugin id from
  the version badge
- Generalize fixVersionedImports in manage-versions.mjs to walk every
  section's snapshot and rewrite ../../src/ and ../../data/ imports,
  catching admin_docs and components files that previous version cuts
  would have broken
- Remove orphan files: developer_portal_versions.json,
  tutorials_versions.json, and stray empty versions.json files inside
  components/ and developer_docs/ content directories

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

@@ -0,0 +1,60 @@
+---
+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
+  parameters={undefined}
+>
+
+</ParamsDetails>
+
+<RequestSchema
+  {...require("./get-all-available-domains.RequestSchema.json")}
+>
+
+</RequestSchema>
+
+<StatusCodes
+  {...require("./get-all-available-domains.StatusCodes.json")}
+>
+
+</StatusCodes>