Add brand autocomplete dropdown to battery add and device install forms

Uses HTML datalist populated from distinct brands in the battery table.
Removed autocomplete="off" which suppresses datalist in Chrome/Chromium.

app.py

@@ -46,8 +46,10 @@ def create_app(config_object="config"):
 
             if not brand:
                 flash("Brand is required.", "error")
+                brands = [r[0] for r in db.query(Battery.brand).distinct().order_by(Battery.brand).all()]
                 return render_template("battery_add.html",
-                                       form_brand="", form_count=1, form_notes=notes or ""), 400
+                                       form_brand="", form_count=1, form_notes=notes or "",
+                                       brands=brands), 400
 
             existing = db.query(func.count(Battery.id)).filter_by(brand=brand).scalar()
             for i in range(count):
@@ -57,7 +59,8 @@ def create_app(config_object="config"):
             flash(f"Added {count} {brand} batter{'y' if count == 1 else 'ies'}.", "success")
             return redirect(url_for("dashboard"))
 
-        return render_template("battery_add.html", form_count=1)
+        brands = [r[0] for r in db.query(Battery.brand).distinct().order_by(Battery.brand).all()]
+        return render_template("battery_add.html", form_count=1, brands=brands)
 
     # ------------------------------------------------------------------ #
     # Battery — detail
@@ -290,7 +293,8 @@ def create_app(config_object="config"):
         device = db.get(Device, device_id)
         if device is None:
             abort(404)
-        return render_template("device_detail.html", device=device)
+        brands = [r[0] for r in db.query(Battery.brand).distinct().order_by(Battery.brand).all()]
+        return render_template("device_detail.html", device=device, brands=brands)
 
     # ------------------------------------------------------------------ #
     # Devices — install batteries

templates/battery_add.html

@@ -9,7 +9,10 @@
     <div class="form-group">
       <label for="brand">Brand <span class="text-danger">*</span></label>
       <input type="text" id="brand" name="brand" value="{{ form_brand|default('') }}"
-             placeholder="e.g. Panasonic Eneloop" required>
+             placeholder="e.g. Panasonic Eneloop" list="brand-list" required>
+      <datalist id="brand-list">
+        {% for b in brands|default([]) %}<option value="{{ b }}">{% endfor %}
+      </datalist>
     </div>
 
     <div class="form-group">

templates/device_detail.html

@@ -29,12 +29,16 @@
   <h2>Install Batteries</h2>
   {% set free_slots = device.battery_slots - device.installed_count() %}
   <p class="text-muted" style="margin-bottom:0.75rem;">{{ free_slots }} slot(s) free</p>
+  <datalist id="brand-list">
+    {% for b in brands|default([]) %}<option value="{{ b }}">{% endfor %}
+  </datalist>
   <form method="post" action="{{ url_for('device_install', device_id=device.id) }}">
     <div style="display:grid;grid-template-columns:1fr auto;gap:0.4rem;max-width:360px;align-items:center;margin-bottom:0.75rem;">
       <span style="font-weight:600;font-size:0.85rem;color:#64748b;">Brand</span>
       <span style="font-weight:600;font-size:0.85rem;color:#64748b;">Qty</span>
       {% for _ in range(4) %}
-      <input type="text" name="brand[]" placeholder="e.g. Eneloop" style="padding:0.3rem 0.5rem;">
+      <input type="text" name="brand[]" placeholder="e.g. Eneloop"
+             list="brand-list" style="padding:0.3rem 0.5rem;">
       <input type="number" name="qty[]" value="0" min="0"
              style="padding:0.3rem 0.5rem;width:4rem;text-align:center;">
       {% endfor %}