feat(backend): complete Module 5 (drop-off points + auto-assign)

drop_off_points (with SPATIAL INDEX on coordinates) +
drop_off_capacity_logs. Public nearby query via ST_Distance_Sphere
returns DOPs sorted by distance with distance_meters in payload.
Admin CRUD plus capacity-log endpoint. Household creation auto-assigns
to the nearest active DOP within 25km; resident can re-run the lookup
via POST /households/{uuid}/reassign-drop-off.

97 feature tests passing.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

app/Http/Requests/DropOff/StoreCapacityLogRequest.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace App\Http\Requests\DropOff;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+class StoreCapacityLogRequest extends FormRequest
+{
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    public function rules(): array
+    {
+        return [
+            'fill_percent' => ['required', 'integer', 'min:0', 'max:100'],
+            'recorded_at' => ['nullable', 'date'],
+            'notes' => ['nullable', 'string', 'max:500'],
+        ];
+    }
+}