Add Schema Followups

1. Reconciliation primitive

• Add src/manifest-reconcile.ts exporting parseManifestStreams, parseSchemaStreams, scanEmittedStreams, reconcile, and reconcileFromDisk. Pure functions only — no globbing or DB access.
• Add 16 unit tests under src/manifest-reconcile.test.ts covering every parser branch and reconcile case (aligned, undeclared-emit, schemaless-emit, ghost-stream, dynamic-emit-miss).
• Add bin/reconcile-manifests.ts CLI that checks schema-bearing connectors by default, finds matching manifests/connectors, reports drift, exits nonzero on any drift, and exposes --all for the broader schemaless-connector audit.
• Add bin/reconcile-manifests.test.ts — regression net that asserts every connector with a schemas.ts aligns. 11 tests today (amazon, chase, chatgpt, claude_code, codex, github, gmail, reddit, slack, usaa, ynab).

2. Pilot fixtures

• Author 42 fixture files (62 total records) at fixtures/<connector>/scrubbed/pilot-real-shape/records/<stream>.jsonl for the six newly-schemed connectors. Authored by sub-agents from schemas.ts + parsers.ts + types.ts; reviewed and replayed.
• Synthetic content uses [REDACTED_*] placeholders for identifying fields. No real owner data, no DB extracts. Records are committable.
• Add bin/replay-pilot-fixtures.ts — diagnostic that replays every committed fixture through validateRecord and reports drift.
• Add src/pilot-fixture-test-helper.ts — registerPilotFixtureTests({ connector, validateRecord }). Each invocation registers one test per stream file; missing fixtures or schema-failing records fail the test loud.
• Add per-connector pilot-fixture.test.ts for github, gmail, ynab, codex, claude_code, slack. Three lines each.

3. zod cleanup

• Replace z.string().url() with z.url() in amazon, chase, usaa schemas (zod 4 idiomatic; deprecation hint cleared).

4. Followups documented

• Update add-polyfill-connector-system/tasks.md usaa row with the schema-replay findings (4 stale-currency records, 2 empty-string records) and the decision: re-ingest, do not loosen schema.
• Confirm reddit re-ingest tracking exists in add-polyfill-layer-two-stream-coverage/tasks.md (it does, both in §1.7 and §1.8). No new tracking needed.

5. Validation gates

• pnpm --dir packages/polyfill-connectors run typecheck clean.
• All previously-existing tests continue to pass.
• 42 new pilot-fixture replay tests pass.
• 11 new fleet-reconciliation tests pass.
• 16 new manifest-reconcile unit tests pass.
• pnpm --dir packages/polyfill-connectors run verify.
• openspec validate add-schema-followups --strict and openspec validate add-schema-validation-coverage --strict.
• openspec validate --all --strict.

6. Out of scope

• USAA data cleanup (re-ingest the 6 stale records). Tracked in add-polyfill-connector-system/tasks.md.
• Reddit re-ingest. Tracked in add-polyfill-layer-two-stream-coverage/tasks.md.
• Browser-daemon retirement. Owner-reviewed separately.
• The 12 connectors with parsers.ts but no schemas.ts (apple_health, github prior to this tranche, ical, imessage, pocket, slack-extra-streams, spotify, strava, twitter_archive, whatsapp, etc.) — out of scope for this change; tracked separately as a connector-by-connector effort.