feat(jobs): embed.text worker (Ollama → vector(1024))

Pads nomic-embed-text's 768 dims to 1024 zeros so a later 1024-dim model
swap is a re-embed, not a migration (per master spec).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

lib/jobs/index.js

@@ -2,8 +2,9 @@ import * as queue from './queue.js';
 import * as echo from './workers/echo.js';
 import * as url from './workers/url.js';
 import * as blob from './workers/blob.js';
+import * as embed from './workers/embed.js';
 
-const WORKERS = [echo, url, blob];
+const WORKERS = [echo, url, blob, embed];
 
 export async function registerWorkers() {
   for (const w of WORKERS) {

lib/jobs/workers/embed.js

@@ -0,0 +1,29 @@
+import { embedText, padTo } from '../../ai/ollama.js';
+import { pool } from '../../db/pool.js';
+import { recordAudit } from '../../db/repos/audit.js';
+
+export const NAME = 'embed.text';
+
+const STRING_BUILDERS = {
+  page: row => `${row.title}\n\n${row.body_md || ''}`,
+  ref: row => `${row.title || ''}\n${row.summary || ''}\n${row.body_text || ''}`,
+  source_doc: row => `${row.name}\n${row.body_text || ''}`,
+  conversation: row => `${row.title || ''}\n${row.summary || ''}`
+};
+
+const TABLE = { page: 'pages', ref: 'refs', source_doc: 'source_docs', conversation: 'conversations' };
+
+export async function handler(job) {
+  const { entity_type, entity_id } = job.data;
+  const table = TABLE[entity_type];
+  if (!table) throw new Error(`unknown entity_type: ${entity_type}`);
+  const { rows: [row] } = await pool.query(`SELECT * FROM ${table} WHERE id=$1`, [entity_id]);
+  if (!row) return { skipped: 'gone' };
+  const text = STRING_BUILDERS[entity_type](row).slice(0, 6_000);
+  const v = await embedText(text);
+  const padded = padTo(v, 1024);
+  const literal = '[' + padded.join(',') + ']';
+  await pool.query(`UPDATE ${table} SET embedding=$1::vector WHERE id=$2`, [literal, entity_id]);
+  await recordAudit({ kind: 'worker', id: null }, 'update', entity_type, entity_id, null, { embedding: 'updated' });
+  return { entity_id };
+}

tests/jobs/workers/embed.test.js

@@ -0,0 +1,53 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
+import { resetDb } from '../../helpers/db.js';
+import { migrateUp } from '../../../lib/db/migrate.js';
+import { stopBoss, waitForJob } from '../../helpers/boss.js';
+import { pool } from '../../../lib/db/pool.js';
+import * as queue from '../../../lib/jobs/queue.js';
+import { registerWorkers } from '../../../lib/jobs/index.js';
+import * as spaces from '../../../lib/db/repos/spaces.js';
+import * as pages from '../../../lib/db/repos/pages.js';
+
+beforeEach(async () => {
+  await resetDb(); await migrateUp(); await queue.start(); await registerWorkers();
+  global.fetch = vi.fn(async () => new Response(
+    JSON.stringify({ embedding: new Array(768).fill(0.42) }),
+    { status: 200, headers: { 'content-type': 'application/json' }}
+  ));
+});
+afterEach(async () => { await stopBoss(); vi.restoreAllMocks(); });
+
+describe('embed.text worker', () => {
+  it('writes a vector(1024) to the page row', async () => {
+    const sp = await spaces.create({ slug: 'e', name: 'E' }, { kind: 'user', id: null });
+    const pg = await pages.create(
+      { space_id: sp.id, slug: 'p', title: 'P', body_md: 'body' },
+      { kind: 'user', id: null }
+    );
+    const id = await queue.enqueue('embed.text', { entity_type: 'page', entity_id: pg.id });
+    const j = await waitForJob('embed.text', id, { timeoutMs: 10_000 });
+    expect(j.state).toBe('completed');
+    const { rows: [row] } = await pool.query(
+      'SELECT embedding::text AS embedding FROM pages WHERE id=$1', [pg.id]
+    );
+    expect(row.embedding).toBeTruthy();
+    // 1024 floats → at least 1023 commas in the literal
+    const commas = (row.embedding.match(/,/g) || []).length;
+    expect(commas).toBe(1023);
+  });
+
+  it('emits an audit log entry', async () => {
+    const sp = await spaces.create({ slug: 'e2', name: 'E2' }, { kind: 'user', id: null });
+    const pg = await pages.create(
+      { space_id: sp.id, slug: 'p', title: 'P', body_md: 'body' },
+      { kind: 'user', id: null }
+    );
+    const id = await queue.enqueue('embed.text', { entity_type: 'page', entity_id: pg.id });
+    await waitForJob('embed.text', id, { timeoutMs: 10_000 });
+    const { rows } = await pool.query(
+      `SELECT * FROM audit_log WHERE entity_type='page' AND entity_id=$1 AND actor_kind='worker'`,
+      [pg.id]
+    );
+    expect(rows.length).toBeGreaterThan(0);
+  });
+});