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/delete-a-css-template.api.mdx

@@ -0,0 +1,68 @@
+---
+id: delete-a-css-template
+title: "Delete a CSS template"
+description: "Delete a CSS template"
+sidebar_label: "Delete a CSS template"
+hide_title: true
+hide_table_of_contents: true
+api: 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
+sidebar_class_name: "delete 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={"Delete a CSS template"}
+>
+</Heading>
+
+<MethodEndpoint
+  method={"delete"}
+  path={"/api/v1/css_template/{pk}"}
+  context={"endpoint"}
+>
+
+</MethodEndpoint>
+
+
+
+Delete a CSS template
+
+<Heading
+  id={"request"}
+  as={"h2"}
+  className={"openapi-tabs__heading"}
+>
+  <Translate id="theme.openapi.request.title">Request</Translate>
+</Heading>
+
+<ParamsDetails
+  {...require("./delete-a-css-template.ParamsDetails.json")}
+>
+
+</ParamsDetails>
+
+<RequestSchema
+  {...require("./delete-a-css-template.RequestSchema.json")}
+>
+
+</RequestSchema>
+
+<StatusCodes
+  {...require("./delete-a-css-template.StatusCodes.json")}
+>
+
+</StatusCodes>