feat(ombi): Add Ombi PALDRA integration for request management

- Add OmbiRetriever extending ArrRetriever for PALDRA compliance
- Add OmbiClient for low-level Ombi API communication
- Add getOmbiInstances() to config.js following multi-instance pattern
- Register Ombi in PALDRA registry with Ombi-specific methods
- Add external ID matching (TMDB/TVDB/IMDB) to Ombi requests
- Update DownloadMatcher to be async and enrich downloads with Ombi links
- Add getOmbiLink/getOmbiSearchLink helpers to DownloadAssembler
- Implement new service icon layout (Ombi + Sonarr/Radarr icons)
- Add CSS styling for service icons
- Update dashboard routes to include Ombi configuration
- Extend OpenAPI with Ombi tag and NormalizedDownload properties
- Update documentation (README, ARCHITECTURE, SECURITY, CHANGELOG)
- Add Ombi configuration to .env.sample

server/services/DownloadAssembler.js

@@ -45,6 +45,23 @@ function getRadarrLink(movie) {
   return `${movie._instanceUrl}/movie/${movie.titleSlug}`;
 }
 
+// Helper to build Ombi request link
+function getOmbiLink(requestId, type, ombiBaseUrl) {
+  if (!requestId || !type || !ombiBaseUrl) return null;
+  return `${ombiBaseUrl}/#/request/${type}/${requestId}`;
+}
+
+// Helper to build Ombi search link
+function getOmbiSearchLink(searchId, type, ombiBaseUrl) {
+  if (!searchId || !type || !ombiBaseUrl) return null;
+  if (type === 'series') {
+    return `${ombiBaseUrl}/#/tv/search/${searchId}`;
+  } else if (type === 'movie') {
+    return `${ombiBaseUrl}/#/movie/search/${searchId}`;
+  }
+  return null;
+}
+
 // Determine if a download can be blocklisted by the current user
 // Admins: always true (they have arrQueueId)
 // Non-admins: true if importIssues OR (torrent >1h old AND availability<100%)
@@ -101,6 +118,8 @@ module.exports = {
   getImportIssues,
   getSonarrLink,
   getRadarrLink,
+  getOmbiLink,
+  getOmbiSearchLink,
   canBlocklist,
   extractEpisode,
   gatherEpisodes