feat(manual-batch): canonical plate + manual mode as default

- canonical_plate (uppercase alnum, strips space/dot/hyphen) at all plate
  write sites; pretty_plate for render (history, XLSX, operator tile) so
  B 1234 XYZ and B1234XYZ are one plate everywhere
- group_dos_by_plate compares canonical plates -> no false mixed_plates
- warn-only (never blocking) plate format hint in operator + monitoring modals
- batch.default_mode: manual (auto merged truck loads when a sack sat in the
  counting ROI); operator banner explains plate -> start -> stop
- docs + AGENTS known-limitation note; 85 tests pass

counter_dashboard.py

@@ -71,12 +71,14 @@ DASHBOARD_HOST = CFG.dashboard.host
 FLASK_DEBUG = CFG.dashboard.debug
 
 from src.do_batch import (
+    canonical_plate,
     empty_do_settings,
     group_dos_by_plate,
     is_valid_batch_mode,
     is_valid_ocr_engine,
     net_counts,
     normalize_batch_mode,
+    pretty_plate,
     OCR_ENGINES,
     retention_cutoff_date,
     should_discard_batch,
@@ -475,7 +477,7 @@ def api_batch_start():
         elif mode == "manual":
             # Legacy manual mode: batch start locked until plate entered.
             req_data = request.get_json(silent=True) or request.form or {}
-            plate = str(req_data.get("plate", "")).strip().upper()
+            plate = canonical_plate(req_data.get("plate", ""))
             if not plate:
                 return jsonify({
                     "success": False,
@@ -982,7 +984,7 @@ def api_do_upload():
                 """,
                 (counting_date, rel,
                  ocr.get("no_do", "") or "",
-                 ocr.get("plate", "") or "",
+canonical_plate(ocr.get("plate")),
                  int(ocr.get("expected_sack") or 0),
                  int(ocr.get("expected_box") or 0),
                  ocr_raw),
@@ -992,7 +994,7 @@ def api_do_upload():
                 "id": do_id,
                 "photo_url": f"/api/do/photo/{do_id}",
                 "no_do": ocr.get("no_do", "") or "",
-                "plate": ocr.get("plate", "") or "",
+                "plate": pretty_plate(ocr.get("plate")),
                 "expected_sack": int(ocr.get("expected_sack") or 0),
                 "expected_box": int(ocr.get("expected_box") or 0),
                 "ocr_text": ocr.get("ocr_text", "") or "",
@@ -1067,7 +1069,7 @@ def api_do_staged():
                 "id": r["id"],
                 "photo_url": f"/api/do/photo/{r['id']}",
                 "no_do": r["no_do"] or ocr.get("no_do", ""),
-                "plate": r["plate"] or ocr.get("plate", ""),
+                "plate": pretty_plate(r["plate"] or ocr.get("plate")),
                 "expected_sack": r["expected_sack"],
                 "expected_box": r["expected_box"],
                 "status": r["status"],
@@ -1111,7 +1113,7 @@ def api_do_item(do_id):
 
         req = request.get_json(silent=True) or {}
         no_do = str(req.get("no_do", "")).strip()
-        plate = str(req.get("plate", "")).strip().upper()
+        plate = canonical_plate(req.get("plate", ""))
         try:
             expected_sack = int(req.get("expected_sack", 0) or 0)
             expected_box = int(req.get("expected_box", 0) or 0)
@@ -1267,7 +1269,7 @@ def api_current_batch():
                     "unloading": data.get("unloading", 0),
                     "net_sack": net_sack,
                     "net_box": net_box,
-                    "plate": data.get("plate", "") or "",
+                    "plate": pretty_plate(data.get("plate")),
                     "do_numbers": data.get("do_numbers") or [],
                     "expected_sack": int(data.get("expected_sack", 0) or 0),
                     "expected_box": int(data.get("expected_box", 0) or 0),
@@ -1344,7 +1346,7 @@ def api_previous_batch():
                     "count": row["count"],
                     "box_loading": row["box_loading"],
                     "model_mode": row["model_mode"],
-                    "plate": row["plate"] if "plate" in row.keys() else "",
+                    "plate": pretty_plate(row["plate"]),
                     "do_numbers": do_numbers,
                     "expected_sack": row["expected_sack"] if "expected_sack" in row.keys() else 0,
                     "expected_box": row["expected_box"] if "expected_box" in row.keys() else 0,
@@ -1507,7 +1509,7 @@ def api_day_detail(date):
                     "count": row["count"],
                     "box_loading": row["box_loading"],
                     "model_mode": row["model_mode"],
-                    "plate": row["plate"] if "plate" in row.keys() else "",
+                    "plate": pretty_plate(row["plate"]),
                     "do_numbers": do_numbers,
                     "expected_sack": row["expected_sack"] if "expected_sack" in row.keys() else 0,
                     "expected_box": row["expected_box"] if "expected_box" in row.keys() else 0,
@@ -1990,7 +1992,7 @@ def export_day_xlsx(date):
         ws.cell(row=r_idx, column=1, value=row["batch_number"])
         ws.cell(row=r_idx, column=2, value=row["count"])
         ws.cell(row=r_idx, column=3, value=row["box_loading"])
-        ws.cell(row=r_idx, column=4, value=row["plate"] if "plate" in row.keys() else "")
+        ws.cell(row=r_idx, column=4, value=pretty_plate(row["plate"]))
         ws.cell(row=r_idx, column=5, value=", ".join(do_numbers))
         ws.cell(row=r_idx, column=6, value=row["expected_sack"] if "expected_sack" in row.keys() else 0)
         ws.cell(row=r_idx, column=7, value=row["expected_box"] if "expected_box" in row.keys() else 0)