Update column docs for normalized crop/diagnosis

README.md

@@ -70,10 +70,8 @@ low-confidence diagnosis). Each membership is its own row in `metadata.csv`, sha
 | `category` | One of the 8 categories above |
 | `country` | Country the submission came from |
 | `month` | Year-month the photo was submitted (YYYY-MM) |
-| `crop` | Crop identified in the photo, where resolved |
-| `diagnosis` | Diagnosis returned, where resolved |
-| `health_status` | `Healthy` / `Disease` / `Unknown` / `not_applicable` |
-| `confidence` | Reported confidence of the diagnosis, where applicable |
+| `crop` | Crop identified in the photo, where resolved. Normalized to a standard set of names (synonyms merged, casing standardized) |
+| `diagnosis` | Diagnosis identified, where resolved. Normalized the same way — not a pass-through of any single service's raw label |
 | `livestock_signal` | `Yes` / `No` / `Unknown` — whether the submission was flagged as livestock-related |
 | `query_present` | Whether the farmer sent text alongside the photo |
 | `farmer_query` | Farmer's question, in the original language, PII-redacted |