make cluster page searchable (#616)

* Initial plan

* Add search functionality to clusters page for searching within tabs

Co-authored-by: LukasWallrich <60155545+LukasWallrich@users.noreply.github.com>

* Fix code review issues: improve regex handling and DOM manipulation

Co-authored-by: LukasWallrich <60155545+LukasWallrich@users.noreply.github.com>

* Redesign cluster search as collapsible sidebar (#650)

* Initial plan

* Redesign cluster search as collapsible left sidebar

Co-authored-by: LukasWallrich <60155545+LukasWallrich@users.noreply.github.com>

* Fix code review feedback: use alert-info for no results and prevent layout shift

Co-authored-by: LukasWallrich <60155545+LukasWallrich@users.noreply.github.com>

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: LukasWallrich <60155545+LukasWallrich@users.noreply.github.com>

* [WIP] Fix search function layout on cluster page (#654)

* Initial plan

* Fix search panel visibility and scroll behavior

Co-authored-by: LukasWallrich <60155545+LukasWallrich@users.noreply.github.com>

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: LukasWallrich <60155545+LukasWallrich@users.noreply.github.com>
Co-authored-by: Lukas Wallrich <lukas.wallrich@gmail.com>

* fix: improve clusters search panel UX

- Auto-hide panel when clicking search result
- Position panel below navbar to avoid hiding logo
- Reduce panel width to 70% on mobile devices
- Show only search icon on mobile toggle button

* Improve cluster search: searchable titles and scroll to match

- Make cluster titles and tab labels searchable (e.g., searching "QRP"
  now finds the "QRPs" tab)
- Search section description text outside of tabs
- Scroll to the first highlighted match within a tab pane instead of
  the cluster section top
- Handle section-level results (description/title matches)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* Per-paragraph results, live search, fix cluster title display

- Show one result per matching paragraph/reference instead of per tab
- Filter out nested blocks (p inside li) to avoid duplicate results
- Fix cluster name: use h1 (actual title) not h3 ("Description")
- Live search as user types with 300ms debounce
- Make tab labels searchable (e.g. "QRP" finds "QRPs" tab)
- Scroll to the specific matched element, not the section top

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* Extend cluster search to include titles and descriptions

The search previously only searched within tab panes. Now also searches
cluster titles and description content outside tabs.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: Richard Dushime <45734838+richarddushime@users.noreply.github.com>
Co-authored-by: richarddushime <mudaherarich@gmail.com>
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: 4 people

layouts/partials/custom_js.html

@@ -0,0 +1,6 @@
+{{/* Custom JavaScript for FORRT site */}}
+
+{{/* Include clusters search functionality on clusters page */}}
+{{ if eq .RelPermalink "/clusters/" }}
+<script src="{{ "js/clusters-search.js" | relURL }}"></script>
+{{ end }}