Add size, chemistry, capacity, purchase date to bulk add form

Shared metadata fields settable at creation time apply to all
batteries in the batch, avoiding per-battery detail page visits.

app.py

@@ -37,10 +37,11 @@ def create_app(config_object="config"):
     @app.route("/battery/add", methods=["GET", "POST"])
     def battery_add():
         if request.method == "POST":
-            brand = request.form.get("brand", "").strip()
-            notes = request.form.get("notes", "").strip() or None
+            f = request.form
+            brand = f.get("brand", "").strip()
+            notes = f.get("notes", "").strip() or None
             try:
-                count = max(1, min(50, int(request.form.get("count", 1) or 1)))
+                count = max(1, min(50, int(f.get("count", 1) or 1)))
             except (ValueError, TypeError):
                 count = 1
 
@@ -51,10 +52,24 @@ def create_app(config_object="config"):
                                        form_brand="", form_count=1, form_notes=notes or "",
                                        brands=brands), 400
 
+            def _int(key):
+                v = f.get(key, "").strip()
+                try:
+                    return int(v) if v else None
+                except ValueError:
+                    return None
+
+            size          = f.get("size", "").strip() or None
+            chemistry     = f.get("chemistry", "").strip() or None
+            capacity_mah  = _int("capacity_mah")
+            purchase_date = f.get("purchase_date", "").strip() or None
+
             existing = db.query(func.count(Battery.id)).filter_by(brand=brand).scalar()
             for i in range(count):
                 label = f"{brand} {existing + i + 1:03d}"
-                db.add(Battery(label=label, brand=brand, status="available", notes=notes))
+                db.add(Battery(label=label, brand=brand, status="available", notes=notes,
+                               size=size, chemistry=chemistry,
+                               capacity_mah=capacity_mah, purchase_date=purchase_date))
             db.commit()
             flash(f"Added {count} {brand} batter{'y' if count == 1 else 'ies'}.", "success")
             return redirect(url_for("dashboard"))