Harden conversation replies and prioritize newest candidates

src/database/candidate-queue-repository.ts

@@ -96,10 +96,11 @@ export class CandidateQueueRepository {
       ) VALUES (?, ?, ?, ?, ?, ?, ?, 'discovered', ?, ?, ?)
     `);
 
+    const newestPostsFirst = [...posts].sort((left, right) => right.created_utc - left.created_utc);
     this.db.transaction(() => {
-      for (const [index, post] of posts.entries()) {
+      for (const [index, post] of newestPostsFirst.entries()) {
         if (result.discovered >= maxNewCandidates) {
-          result.deferredAtCapacity += posts.length - index;
+          result.deferredAtCapacity += newestPostsFirst.length - index;
           break;
         }
         if (existingPost.get(post.id)) {
@@ -214,7 +215,7 @@ export class CandidateQueueRepository {
       WHERE post_id IN (
         SELECT post_id FROM candidate_queue
         WHERE status = 'retryable' AND available_at <= ?
-        ORDER BY priority DESC, discovered_at ASC
+        ORDER BY post_created_at DESC, priority DESC, discovered_at ASC
         LIMIT ?
       )
     `).run(now, now, capacity).changes;
@@ -302,15 +303,8 @@ export class CandidateQueueRepository {
       SELECT * FROM candidate_queue
       WHERE status IN (${ACTIVE_STATUSES.map(() => '?').join(', ')})
       ORDER BY
-        CASE status
-          WHEN 'sending' THEN 1
-          WHEN 'screening' THEN 2
-          WHEN 'ready' THEN 3
-          WHEN 'retryable' THEN 4
-          ELSE 5
-        END,
-        priority DESC,
         post_created_at DESC,
+        priority DESC,
         discovered_at ASC
       LIMIT ?
     `).all(...ACTIVE_STATUSES, limit) as Array<Record<string, unknown>>;
@@ -332,7 +326,7 @@ export class CandidateQueueRepository {
       const row = this.db.prepare(`
         SELECT post_id FROM candidate_queue
         WHERE status = ? AND available_at <= ? ${requirePrepared ? 'AND prepared_json IS NOT NULL' : ''}
-        ORDER BY priority DESC, post_created_at DESC, discovered_at ASC
+        ORDER BY post_created_at DESC, priority DESC, discovered_at ASC
         LIMIT 1
       `).get(from, now) as { post_id: string } | undefined;
       if (!row) return null;