feat(seo): AI summary enrichment backfill (slice 3) - #113

The ai_summary column comment said to "prefer over description for
structured-data SoftwareApplication.description" — this contradicts the
accepted recovery plan's anti scaled-content-abuse guardrail
(specs/stage-6-slices/00-recovery-plan.md, "AI summary is a labeled
supplement, never the page body"). Corrected the comment to state the
opposite: labeled supplement only, never substituted into JSON-LD
description or used as page body copy.

Slice 3 of the indexing-recovery plan.

Adds scripts/mcpfind/ai_summary_generate.py — the nightly orchestrator that
backfills ai_summary for gated (isIndexable) servers, per
specs/stage-6-slices/00-recovery-plan.md Slice 3.

- Ports apps/web/lib/indexable.ts#isIndexable to Python 1:1 (same
  README_MIN_LENGTH/MIN_SIGNALS thresholds) so only servers already clearing
  the real-data quality bar get an AI summary.
- Computes a source hash matching migration 006's documented
  ai_summary_source_hash inputs (name|description|readme_content[:8000]|
  category|package_name|package_type|registry_tags) and skips rows whose
  hash is unchanged — idempotent, no wasted regeneration.
- Generates via the local Mac Mini Claude Code queue (127.0.0.1:7600), never
  a raw Anthropic API key, consistent with this org's convention. No prior
  client for that queue existed in this repo (grepped for "7600" and
  "claude-code-local-queue" — no hits outside the migration comments), so
  the request/response contract is documented as an assumption in the
  module docstring; only call_local_queue() needs updating if the real
  contract differs.
- Reads SUPABASE_URL / SUPABASE_SERVICE_ROLE_KEY, matching the existing
  convention in packages/sync/src/index.ts and recategorize-other.ts (the
  anon key is read-only under RLS and cannot write ai_summary_*).
- argparse CLI (--dry-run, --limit, --prompt-version, --page-size,
  --sleep-seconds, -v), structured logging, per-row error isolation so one
  bad row doesn't abort the whole nightly run (exit 2 signals partial
  failure, safe to re-run).

…ytecode

Running the new ai_summary_generate.py script locally generated a .pyc that
got swept into the previous commit's `git add scripts/mcpfind/`. Untrack it
and add __pycache__/ and *.pyc to .gitignore so this doesn't recur — this
repo has no prior Python tooling/gitignore entries to reuse.

… pages

Slice 3 of the indexing-recovery plan
(specs/stage-6-slices/00-recovery-plan.md) — renders ai_summary (migration
006) as a clearly labeled "AI Summary" callout block, positioned near the
top of the main content column, right before the README section.

- packages/shared/src/types.ts: add ai_summary / ai_summary_generated_at to
  Server. Excluded from ServerListItem (same rationale as readme_content —
  detail-page only, not selected by SERVER_LIST_COLUMNS).
- apps/web/lib/queries.ts: SERVER_DETAIL_COLUMNS now selects ai_summary and
  ai_summary_generated_at alongside readme_content.
- apps/web/app/servers/[slug]/page.tsx: new section, rendered only when
  server.ai_summary is non-null, visually distinct (bordered callout,
  IconRobot, "AI Summary" heading) and explicitly labeled as a supplement
  ("supplements, not a substitute for the README below").

Guardrail verified, not changed: apps/web/lib/metadata.ts's
generateServerJsonLd already builds SoftwareApplication.description from
server.description (never ai_summary) — confirmed by reading the function
and grepping the whole apps/+packages/ tree for "ai_summary"; no other
consumer exists. This is the hard guardrail from the recovery plan's
"AI summary is a labeled supplement, never the page body" section.

Verified: pnpm --filter @mcpfind/shared build, pnpm --filter @mcpfind/web
type-check, and pnpm --filter @mcpfind/web test (206/206 passing) all clean
after this change.