seed-mcp scaffold: clone docs-mcp-template, customize for crop_seed PRODUCT_NAME

Sibling project to crop-chem-docs, same MCP-template lineage. Corpus is
seed/hybrid varieties across 6 vendors instead of pesticide labels.

What's customized vs. the template:
- CLAUDE.md: vendor matrix, build priority, Pioneer fallback policy,
  canonical sidecar schema (per-crop), Golden Harvest disease-scale
  reversal gotcha, no-IPv6 / HTTPS-clone note
- README.md: vendor coverage table, tool list, phase status
- Dockerfile: PRODUCT_NAME=crop_seed default, sources.json (not
  bundles.json), HYBRID_SEARCH=true, OLLAMA_URL + RERANK_URL Docker
  DNS defaults (same llama-rerank sidecar as crop-chem-docs)
- .gitea/workflows/refresh.yml: monthly cron (seed catalogs move
  slowly), 5 GREEN scraper steps, corpus-YYYY.MM.DD tag for Drawbar
  pinning, continue-on-error on GC step
- .gitea/workflows/image-only.yml: paths filter + cancel-in-progress
  concurrency group
- scripts/registry_gc.py: lifted from crop-chem-docs (correct Gitea
  packages API URL + UA header to bypass CF block on default
  Python-urllib UA)
- sources.json: catalog of 6 sources + scope_filter + per-source
  schema notes + Pioneer-exclusion rationale
- scrape/runner.py: dispatcher with --all = GREEN-only
- scrape/sources/{bayer_seeds,golden_harvest,nk,agripro,becks_pfr,
  becks_products}.py: stub modules with implementation notes
- docs_mcp/server.py: PRODUCT_NAME default → crop_seed,
  PRODUCT_DOCS_URL → repo URL

Pioneer is intentionally NOT a source. ToS bans automation; dealer
locator is login-gated. The MCP returns a curated fallback lesson
directing the user to pioneer.com.

Next phases:
- Phase 1: implement bayer_seeds (lift-and-shift from crop-chem-docs
  Bayer scraper; same __NEXT_DATA__ infra)
- Phase 7: curate eval/queries.jsonl
- Phase 11: lessons.md with Pioneer fallback + disease-scale notes

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

scrape/sources/becks_pfr.py

@@ -0,0 +1,45 @@
+"""Beck's PFR (Practical Farm Research) scraper.
+
+Source: Public Sanity GROQ API at ``https://mc8v24rf.api.sanity.io``.
+No authentication required — Beck's exposes their CMS content store
+publicly. ~2,089 documents going back to 2015.
+
+Sanity query endpoint:
+  ``/v1/data/query/production?query=<groq>``
+
+Useful GROQ for PFR docs (the projectId / dataset are public):
+
+  *[_type == "pfrStudy"] {
+    _id, title, year, crop, slug, summary, body, attachments
+  }
+
+Records are research studies, not variety identity — head-to-head
+yield trials, fungicide timing, planting-date studies, hybrid-by-
+population, biological seed treatments, etc.
+
+Treat differently from variety scrapers:
+- One record per study, not per variety
+- chunk_0 preamble includes the study's tl;dr finding (extract from
+  the ``summary`` field if present, or first paragraph of ``body``)
+- Crop tag (corn/soy/wheat) for filtering
+- Year tag — older PFR studies are still relevant but search should
+  let the user weight recency
+
+Polite rate limit: Sanity is generous but no auth means we should
+keep concurrency ≤4 and pause ~250ms between batches.
+
+TODO: implement.
+"""
+from __future__ import annotations
+
+import sys
+
+
+def main(argv: list[str] | None = None) -> int:
+    print("becks_pfr: not implemented yet — public Sanity GROQ at mc8v24rf.api.sanity.io, ~2089 research docs",
+          file=sys.stderr)
+    return 2
+
+
+if __name__ == "__main__":
+    sys.exit(main(sys.argv[1:]))