Add ACMCC app source, Supabase backend, and project config

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

supabase/migrations/20260423172058_164595a6-918e-4c23-886e-577bdc053fbf.sql

@@ -0,0 +1,10 @@
+DROP POLICY IF EXISTS "Legal users can view legal matters" ON public.legal_matters;
+
+CREATE POLICY "Legal users can view assigned community legal matters"
+ON public.legal_matters
+FOR SELECT
+TO authenticated
+USING (
+  public.has_role(auth.uid(), 'legal'::public.app_role)
+  AND public.legal_user_assigned_to_association(auth.uid(), association_id)
+);