docker: production image + Gitea Actions for monthly refresh

Dockerfile: self-contained image with corpus + Chroma + BM25 baked
in. Drawbar's compose pulls + runs without volume mounts. Built from
sources.json (labels schema), PRODUCT_NAME=crop_chem by default,
HYBRID_SEARCH=true (always-on for production quality). RERANK_URL +
OLLAMA_URL get set at compose time.

.gitea/workflows/refresh.yml: monthly cron (1st @ 06:00 UTC) does
full scrape → reindex → image push. Scrapes Bayer (~30 min) +
EPA PPLS row-crop filtered (~7h). Skips reindex+push if no corpus
diff. Tags pushed: :latest, :<sha12>, :corpus-<YYYY.MM.DD>.

.gitea/workflows/image-only.yml: on-demand or auto on code-only
pushes to main (paths: docs_mcp/, rag/, scrape/, requirements.txt,
Dockerfile, sources.json). Reindexes from committed corpus, builds
image, pushes. ~10 min vs ~9h full refresh.

.gitignore: corpus/ now COMMITTED (4,159 labels, 265 MB of .md +
sidecars). Lets image-only.yml rebuild indexes without re-scraping.
chroma/ + bm25/ still gitignored (regenerable binary indexes).

.dockerignore: drops venv, eval results, PLAN/README/CLAUDE.md,
deploy/, .git/ — keeps the image lean. corpus + chroma + bm25
explicitly NOT in dockerignore (those go INTO the image).

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

corpus/epa_ppls/352-396.md

@@ -0,0 +1,17 @@
+# DUPONT BENLATE DF FUNGICIDE
+
+- EPA Reg No: **352-396**
+- Registrant: CORTEVA AGRISCIENCE, LLC
+- Signal word: Caution
+- Active ingredients: Benomyl (75%)
+- Label accepted: 1981-10-13
+- Source PDF: https://www3.epa.gov/pesticides/chem_search/ppls/000352-00396-19811013.pdf
+
+---
+---- .. ~-
+• 
+E. J. DU PONT DE NEMOURS & CO. [INC.! • BIOCHEMICAlS DEPARTMENT, WILMINGTON, DE 
+I 
+• 
+• 
+- - ------------------------------------~J