feat(admin-ui): sub-room caps and test-case issue linking

Two admin screens for work that previously had server support but no way to
reach it.

Rooms → a room → Sub-rooms: per-sub-room max players, with the room's own
advertised capacity shown alongside so the two are not mistaken for each other.
Each row also shows whether the sub-room is a matchmaking target and which blob
it loads.

Activity → Test cases: file a GitHub issue against a case, follow the link, or
unlink it, plus a reconcile button. Filing is idempotent server-side, so the
button is safe to press twice. When GitHub is unconfigured the actions disable
themselves and the page explains why rather than failing on click — a server
with no token is an ordinary deployment.

Both go in as tabs on the existing hub pages rather than new sidebar entries,
matching how the nav is organised.

Server side adds GET api/admin/v1/testcases (the list the SPA renders, with
each case's issue number) and mirrors the three issue routes under
/api/admin/v1/testcases/... because the SPA's client speaks that prefix
exclusively.

I had told the user this UI was not possible on this branch because
wwwroot/admin holds a built bundle. That was wrong — the source is in
DorkNet.Server/admin-ui and builds to it.

DorkNet.Server/Controllers/API/TestCaseManagement/TestCaseIssuesController.cs

@@ -36,6 +36,47 @@ public class TestCaseIssuesController(
     private const int StatusFailed = 2;
     private const int StatusPassed = 3;
 
+
+    /// <summary>GET <c>api/admin/v1/testcases</c> — every test case with its
+    /// issue link, newest pass first. Optional <c>?passId=</c> narrows to one
+    /// test pass and <c>?status=</c> to one status.
+    ///
+    /// Exists because the admin SPA speaks <c>/api/admin/v1</c> exclusively and
+    /// the client-facing test-case routes are shaped for the in-game QA tab
+    /// (per-pass, no issue fields).</summary>
+    [HttpGet("api/admin/v1/testcases")]
+    public async Task<IActionResult> ListCases(
+        [FromQuery] uint? passId, [FromQuery] int? status, CancellationToken ct)
+    {
+        var query = db.TestCases.AsQueryable();
+        if (passId is uint pass) query = query.Where(c => c.TestPassId == pass);
+        if (status is int s) query = query.Where(c => c.Status == s);
+
+        var cases = await query
+            .OrderByDescending(c => c.TestPassId)
+            .ThenBy(c => c.Key)
+            .Take(500)
+            .ToListAsync(ct);
+
+        return Ok(new
+        {
+            githubConfigured = github.IsConfigured,
+            repository = github.Repository,
+            cases = cases.Select(c => new
+            {
+                c.Id,
+                c.Key,
+                c.Title,
+                c.RoomName,
+                c.Status,
+                c.TestPassId,
+                issueUrl = c.JiraBugUrl,
+                issueNumber = GitHubIssueService.IssueNumberFromUrl(c.JiraBugUrl),
+                c.UpdatedAt,
+            }).ToList(),
+        });
+    }
+
     /// <summary>POST <c>api/testcasemanagement/v1/testcase/{id}/issue</c> —
     /// file a GitHub issue for a test case and link it.
     ///
@@ -44,6 +85,7 @@ public class TestCaseIssuesController(
     /// pass is therefore safe, which is the whole point — the alternative is a
     /// tester filing the same bug on every run.</summary>
     [HttpPost("api/testcasemanagement/v1/testcase/{id}/issue")]
+    [HttpPost("api/admin/v1/testcases/{id}/issue")]
     public async Task<IActionResult> CreateIssue(string id, CancellationToken ct)
     {
         if (!github.IsConfigured)
@@ -81,6 +123,7 @@ public class TestCaseIssuesController(
     /// unlink, leaving the issue itself alone. Closing someone's issue as a
     /// side effect of tidying a QA link would be the wrong call.</summary>
     [HttpDelete("api/testcasemanagement/v1/testcase/{id}/issue")]
+    [HttpDelete("api/admin/v1/testcases/{id}/issue")]
     public async Task<IActionResult> UnlinkIssue(string id, CancellationToken ct)
     {
         var tc = await db.TestCases.FirstOrDefaultAsync(c => c.Id == id, ct);
@@ -112,6 +155,7 @@ public class TestCaseIssuesController(
     /// change, so a case a tester has Claimed, or one nobody has run yet, is
     /// never rewritten underneath them.</summary>
     [HttpPost("api/testcasemanagement/v1/issues/sync")]
+    [HttpPost("api/admin/v1/testcases/issues/sync")]
     public async Task<IActionResult> Sync(CancellationToken ct)
     {
         if (!github.IsConfigured)