FEAT-8b: spreadsheet import tooling (stages 1-2) + review report

tools/import/ (Python, zero-dep migration tooling, not product code):
- xlsx_util.py: dependency-free .xlsx reader (shared strings, cells, drawing anchors)
- genotype.py: notation -> frozen 8-locus mapping + verbatim rawGenotype + unmappedTokens; '-' -> '?'
- extract.py: 10 Stammbaum charts + Wurfchronik -> animals.json/litters.json + anchor-mapped photos;
  dedup on normalise(name)+DOB -> German review-report.md (no DB load)

Run: 889 raw -> 587 unique animals, 24 conflicts, 310 ambiguous, 123 photos, 752 litters.
Output gitignored except review-report.md. Re-runnable per file (Wurfchronik Teil2+).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tools/import/README.md

@@ -0,0 +1,58 @@
+# GerbilManager import tooling (FEAT-8b)
+
+One-off **migration tooling** (Python, no third-party deps) that turns Julian's
+wife's hand-built spreadsheets into normalised JSON for review and, later, import.
+This is *not* product code — it lives outside the app and is run manually.
+
+See the format analysis in `FEAT-8a-format-spec.md` (Pam's hive workspace).
+
+## What it does
+
+`extract.py` runs **stages 1–2** of the pipeline:
+
+1. **Extract (stage 1)**
+   - 10 *Stammbaum* pedigree charts → animals (name, DOB, death, Farbschlag,
+     genotype, breeder, positionally-reconstructed parent links, photos).
+   - *Wurfchronik* litter chronicle → litters (date, dam, sire, Wurfstärke,
+     sex breakdown, Zuchtnummer, notes). Columns are read **by header row** because
+     the two sheets use different schemas.
+   - Embedded photos (`xl/media`) → `output/photos/<animal-slug>/`, mapped to the
+     animal by drawing anchor position.
+2. **Dedup + review (stage 2)**
+   - Merge animals on `normalise(name) + DOB` (corroborated by DOB+genotype).
+   - Emit a German-language `output/review-report.md` for the breeder to verify
+     (merges, **conflicts**, ambiguous/incomplete entries, unmapped genotype tokens).
+   - **Nothing is loaded into the database** — stage 3 (API load) is separate and
+     waits on DATA-2 + FEAT-1b phase 2.
+
+Genotypes are mapped to the frozen 8-locus contract (A C D E G P Sp Re) while
+preserving everything: `genotype.mapped8locus`, `genotype.rawGenotype` (verbatim),
+`genotype.unmappedTokens` (e.g. the `Uw` locus, markers `WFNZ/WP/DP`). A `-`
+(unknown second allele) maps to `?`.
+
+## Run
+
+```sh
+cd tools/import
+python extract.py                       # uses the default source paths
+python extract.py --stammbaeume "<dir>" --wurfchronik "<file.xlsx>"
+```
+
+Requires Python 3. **Re-runnable / idempotent** — re-run when more files arrive
+(Wurfchronik `Teil2+`, or new charts).
+
+## Output (`tools/import/output/`, git-ignored except the report)
+
+| File | Contents |
+|---|---|
+| `animals.json` | deduped animals with genotype, parentRefs, photos, sourceFiles |
+| `litters.json` | litters from the Wurfchronik |
+| `photos/<slug>/…` | extracted, anchor-mapped images |
+| `review-report.md` | **human review deliverable** (committed) |
+
+## Files
+
+- `xlsx_util.py` — dependency-free `.xlsx` reader (zip + XML): shared strings,
+  cells by reference, image/drawing anchors.
+- `genotype.py` — genotype notation parser → 8-locus mapping + raw + unmapped.
+- `extract.py` — the pipeline (stages 1–2).