feat: replace /archive with release-cardinal searchable browser (Phase 9 §8.H)

Retire the three-card overview for a search + medium + genre browser over all
releases. Adds q/genre filter params to the api/release paged read path,
mirroring the existing api/track/page TrackFilter pattern.

DeepDrftData/IReleaseService.cs

@@ -12,10 +12,10 @@ namespace DeepDrftData;
 /// </summary>
 public interface IReleaseService
 {
-    /// <summary>Paginated releases, optionally filtered to one medium. The matching medium's metadata satellite is included in the result. Omit medium for all releases.</summary>
+    /// <summary>Paginated releases, optionally narrowed by medium and a free-text/genre filter. The matching medium's metadata satellite is included in the result. Omit medium for all releases; omit filter for no search/genre narrowing.</summary>
     Task<ResultContainer<PagedResult<ReleaseDto>>> GetPagedAsync(
         int page, int pageSize, string? sortColumn, bool sortDescending,
-        ReleaseMedium? medium, CancellationToken cancellationToken = default);
+        ReleaseMedium? medium, ReleaseFilter? filter = null, CancellationToken cancellationToken = default);
 
     /// <summary>Single release with both metadata navs included (nulls for non-matching media).</summary>
     Task<ResultContainer<ReleaseDto?>> GetByIdAsync(long id, CancellationToken cancellationToken = default);

DeepDrftData/ReleaseManager.cs

@@ -42,7 +42,7 @@ public class ReleaseManager : IReleaseService
 
     public async Task<ResultContainer<PagedResult<ReleaseDto>>> GetPagedAsync(
         int page, int pageSize, string? sortColumn, bool sortDescending,
-        ReleaseMedium? medium, CancellationToken cancellationToken = default)
+        ReleaseMedium? medium, ReleaseFilter? filter = null, CancellationToken cancellationToken = default)
     {
         try
         {
@@ -54,7 +54,9 @@ public class ReleaseManager : IReleaseService
                 IsDescending = sortDescending,
             };
 
-            var entityPage = await _repository.GetPagedByMediumAsync(parameters, medium, cancellationToken);
+            // Collapse an all-null filter to null so the repository skips the predicate block entirely.
+            var effectiveFilter = filter is { IsEmpty: false } ? filter : null;
+            var entityPage = await _repository.GetPagedByMediumAsync(parameters, medium, effectiveFilter, cancellationToken);
 
             var releaseIds = entityPage.Items.Select(r => r.Id).ToList();
             var counts = await _repository.GetTrackCountsByReleaseIdsAsync(releaseIds, cancellationToken);

DeepDrftData/Repositories/ReleaseRepository.cs

@@ -1,4 +1,5 @@
 using DeepDrftData.Data;
+using DeepDrftModels.DTOs;
 using DeepDrftModels.Entities;
 using DeepDrftModels.Enums;
 using Microsoft.EntityFrameworkCore;
@@ -36,17 +37,37 @@ public class ReleaseRepository
             _ => query
         };
 
-    // Paged, optionally medium-filtered release list. The matching medium's satellite is Include'd;
-    // total count reflects the medium filter (applied before Skip/Take).
+    // Paged release list, optionally narrowed by medium and a free-text/genre filter. The matching
+    // medium's satellite is Include'd; total count reflects every applied predicate (all before
+    // Skip/Take). The filter predicates mirror TrackRepository.GetPagedFilteredAsync so the release
+    // browse path searches and filters identically to the track path.
     public async Task<PagedResult<ReleaseEntity>> GetPagedByMediumAsync(
         PagingParameters<ReleaseEntity> paging,
         ReleaseMedium? medium,
+        ReleaseFilter? filter,
         CancellationToken ct)
     {
         IQueryable<ReleaseEntity> query = _context.Releases.Where(r => !r.IsDeleted);
         if (medium.HasValue)
             query = query.Where(r => r.Medium == medium.Value);
 
+        if (filter is not null)
+        {
+            if (!string.IsNullOrWhiteSpace(filter.SearchText))
+            {
+                // Postgres case-insensitive LIKE. The '%' wraps make it a contains-match; ILike is
+                // EF-translatable where ToLower().Contains() is not. Title/Artist are non-null columns
+                // on the release itself, so no navigation guard is needed (unlike the track path).
+                var pattern = $"%{filter.SearchText}%";
+                query = query.Where(r =>
+                    EF.Functions.ILike(r.Title, pattern)
+                    || EF.Functions.ILike(r.Artist, pattern));
+            }
+
+            if (!string.IsNullOrWhiteSpace(filter.Genre))
+                query = query.Where(r => r.Genre == filter.Genre);
+        }
+
         query = ApplyMediumInclude(query, medium);
 
         var totalCount = await query.CountAsync(ct);