Add hard deps on Metatag and Simple Sitemap; implement Metatag summary (/admin/seo/myrest_route_metatag/list) and Metatag settings hub (/admin/seo/myrest_metatag), preserving legacy behavior

Problem/Motivation

MyREST SEO historically provided quick access to Metatag and Simple Sitemap pages and a Metatag “routes/summary” view. The current 1.0.x needs to:
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Re-introduce the summary page for Metatag Defaults (overview of bundles/targets with quick “Edit” links).
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Provide a stable “Metatag settings” hub/redirect route that works across Metatag versions.
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Make the integration predictable by declaring hard dependencies on Metatag and Simple Sitemap, so SEO links are always functional and not dead.

Proposed resolution

1)
Declare hard dependencies in myrest_seo.info.yml:
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dependencies:
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drupal:metatag
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drupal:simple_sitemap (Note: we keep Composer of module clean; site-level composer requires these.)

2)
Implement two new routes under MyREST SEO admin menu:
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myrest_seo.route_metatag_list → /admin/seo/myrest_route_metatag/list
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Controller: builds a table from Metatag Defaults config entities (metatag_defaults.*).
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Columns: Target (global/node type/taxonomy etc.), Applies to (bundle/route), Status (has overrides), Action (Edit link).
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Cacheability: tags config:metatag_defaults, contexts languages:language_interface.
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Access: administer myrest_seo, _admin_route: TRUE.
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myrest_seo.myrest_metatag → /admin/seo/myrest_metatag
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Safe redirect/hub to Metatag defaults collection (e.g., entity.metatag_defaults.collection) or to a known Metatag admin route; if route name differs by version, try a small list and fall back sensibly.
3)
Menu integration (/admin/seo): add two items
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“Metatag (routes/summary)” → list route above.
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“Metatag settings” → hub/redirect above.
4)
UX/Docs
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Keep existing quick links to Simple Sitemap and Robots.txt.
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Update README + Help (hook_help) with the two new paths and purpose.

5)
Tests
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Functional test for the summary page: 200 for admin, 403 for user without permission; at least one row rendered when Metatag Defaults exist; “Edit” link points to edit form.
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Functional test for the hub: resolves/redirects (302 or 200) to a valid Metatag admin page, not back to /admin/seo.