feat: two-step issue resolution (resolve then delete)

- New PATCH /issues/{id} endpoint to toggle resolved flag
- Add resolved:false to new issues
- Frontend: click "✓ Resolve" marks issue green with strikethrough
- Resolved issues show "↺ Reopen" and "🗑 Delete" buttons
- Delete requires confirmation
- Sort: unresolved first, then resolved
- Issues persist until explicitly deleted

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

static/style.css

@@ -2664,12 +2664,35 @@ table.ts-allegiance td:first-child {
 .issue-row {
   padding: 6px 8px;
   border-bottom: 1px solid #333;
+  border-left: 3px solid transparent;
+  color: #ddd;
 }
 
 .issue-row:hover {
   background: #1a1a2a;
 }
 
+.issue-row .issue-description {
+  color: #aaa;
+  font-size: 0.75rem;
+  margin-top: 2px;
+  padding-left: 4px;
+}
+
+.issue-row.issue-resolved {
+  background: rgba(74, 170, 74, 0.12);
+  border-left-color: #4a4;
+}
+
+.issue-row.issue-resolved strong {
+  text-decoration: line-through;
+  color: #888;
+}
+
+.issue-row.issue-resolved .issue-description {
+  color: #666;
+}
+
 .issue-category {
   display: inline-block;
   padding: 1px 6px;
@@ -2680,15 +2703,20 @@ table.ts-allegiance td:first-child {
   text-transform: uppercase;
 }
 
-.issue-resolve-btn {
+.issue-resolve-btn,
+.issue-reopen-btn,
+.issue-delete-btn {
   padding: 1px 6px;
   font-size: 0.65rem;
   background: transparent;
-  color: #4a4;
-  border: 1px solid #4a4;
   cursor: pointer;
   border-radius: 3px;
-  margin-left: 8px;
+  margin-left: 4px;
+}
+
+.issue-resolve-btn {
+  color: #4a4;
+  border: 1px solid #4a4;
 }
 
 .issue-resolve-btn:hover {
@@ -2696,6 +2724,26 @@ table.ts-allegiance td:first-child {
   color: #fff;
 }
 
+.issue-reopen-btn {
+  color: #88a;
+  border: 1px solid #88a;
+}
+
+.issue-reopen-btn:hover {
+  background: #88a;
+  color: #fff;
+}
+
+.issue-delete-btn {
+  color: #c44;
+  border: 1px solid #c44;
+}
+
+.issue-delete-btn:hover {
+  background: #c44;
+  color: #fff;
+}
+
 .issues-form {
   padding: 6px 8px;
   border-top: 1px solid #444;