Add permalink anchors to comments and GET comment-by-ID API

- Comment dates are now clickable anchor links (#comment-{id})
- Pages scroll to and highlight the target comment when URL has a hash
- Added GET /api/issues/:id/comments/:commentId endpoint
- Updated skill docs with new endpoint and comment URL format

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/services/issues.ts

@@ -779,6 +779,13 @@ export function issueService(db: Db) {
         .where(eq(issueComments.issueId, issueId))
         .orderBy(desc(issueComments.createdAt)),
 
+    getComment: (commentId: string) =>
+      db
+        .select()
+        .from(issueComments)
+        .where(eq(issueComments.id, commentId))
+        .then((rows) => rows[0] ?? null),
+
     addComment: async (issueId: string, body: string, actor: { agentId?: string; userId?: string }) => {
       const issue = await db
         .select({ companyId: issues.companyId })