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/components/TODO.md

@@ -0,0 +1,71 @@
+---
+title: Components TODO
+sidebar_class_name: hidden
+---
+
+# Components TODO
+
+These components were found but not yet supported for documentation generation.
+Future phases will add support for these sources.
+
+## Summary
+
+- **Total skipped:** 19 story files
+- **Reason:** Import path resolution not yet implemented
+
+## Skipped by Source
+
+### App Components
+
+9 components
+
+- [ ] `superset-frontend/src/components/AlteredSliceTag/AlteredSliceTag.stories.tsx`
+- [ ] `superset-frontend/src/components/Chart/DrillDetail/DrillDetailTableControls.stories.tsx`
+- [ ] `superset-frontend/src/components/CopyToClipboard/CopyToClipboard.stories.tsx`
+- [ ] `superset-frontend/src/components/ErrorMessage/ErrorAlert.stories.tsx`
+- [ ] `superset-frontend/src/components/FacePile/FacePile.stories.tsx`
+- [ ] `superset-frontend/src/components/FilterableTable/FilterableTable.stories.tsx`
+- [ ] `superset-frontend/src/components/RowCountLabel/RowCountLabel.stories.tsx`
+- [ ] `superset-frontend/src/components/Tag/Tag.stories.tsx`
+- [ ] `superset-frontend/src/components/TagsList/TagsList.stories.tsx`
+
+### Dashboard Components
+
+2 components
+
+- [ ] `superset-frontend/src/dashboard/components/AnchorLink/AnchorLink.stories.tsx`
+- [ ] `superset-frontend/src/dashboard/components/nativeFilters/FilterBar/FilterControls/FilterDivider.stories.tsx`
+
+### Explore Components
+
+4 components
+
+- [ ] `superset-frontend/src/explore/components/ControlHeader.stories.tsx`
+- [ ] `superset-frontend/src/explore/components/RunQueryButton/RunQueryButton.stories.tsx`
+- [ ] `superset-frontend/src/explore/components/controls/BoundsControl.stories.tsx`
+- [ ] `superset-frontend/src/explore/components/controls/SliderControl.stories.tsx`
+
+### Feature Components
+
+2 components
+
+- [ ] `superset-frontend/src/features/datasets/AddDataset/DatasetPanel/DatasetPanel.stories.tsx`
+- [ ] `superset-frontend/src/features/home/LanguagePicker.stories.tsx`
+
+### Filter Components
+
+2 components
+
+- [ ] `superset-frontend/src/filters/components/Range/RangeFilterPlugin.stories.tsx`
+- [ ] `superset-frontend/src/filters/components/Select/SelectFilterPlugin.stories.tsx`
+
+## How to Add Support
+
+1. Determine the correct import path for the source
+2. Update `generate-superset-components.mjs` to handle the source
+3. Add source to `SUPPORTED_SOURCES` array
+4. Re-run the generator
+
+---
+
+*Auto-generated by generate-superset-components.mjs*