Refactor web health checker & domain expectations (filter-based)

- Move all domain→expected-status mapping to filter `web_health_expectations`.
- Require explicit app selection via non-empty `group_names`; only those apps are included.
- Add `www_enabled` flag (wired via `WWW_REDIRECT_ENABLED`) to generate/force www.* → 301.
- Support `redirect_maps` to include manual redirects (sources forced to 301), independent of app selection.
- Aliases always 301; canonicals use per-key override or `server.status_codes.default`, else [200,302,301].
- Remove legacy fallbacks (`server.status_codes.home` / `landingpage`).
- Wire filter output into systemd ExecStart script as JSON expectations.
- Normalize various templates to use `to_json` and minor spacing fixes.
- Update app configs (e.g., YOURLS default=301; Confluence default=302; Bluesky web=405; MediaWiki/Confluence canonical/aliases).
- Constructor now uses `WWW_REDIRECT_ENABLED` for domain generation.

Tests:
- Add comprehensive unit tests for filter: selection by group, keyed/default codes, aliases, www handling, redirect_maps, input sanitization.
- Add unit tests for the standalone checker script (JSON parsing, OK/mismatch counting, sanitization).

See conversation: https://chatgpt.com/share/68c2b93e-de58-800f-8c16-ea05755ba776

roles/web-app-desktop/vars/menu_categories.yml

@@ -104,12 +104,20 @@ portfolio_menu_categories:
       - yourls
 
   Presentation:
-    description: "Presentation and Documentation Tools"
+    description: "Presentation Tools"
     icon: "fas fa-tools"
     tags:
       - presentation
       - sphinx
       - portfolio
+  
+  Documentation:
+    description: "Documentation and Wiki Applications"
+    icon: "fa fa-book"
+    tags:
+      - confluence
+      - xwiki
+      - mediawiki
 
   Finance & Accounting:
     description: "Financial and accounting software"
@@ -174,5 +182,4 @@ portfolio_menu_categories:
       - publishing
       - website
       - joomla
-      - mediawiki
       - wordpress