feat: add membership_type column to storage_module for multi-scope storage

- Add membership_type int column (NULL = app-level AuthzMembership, non-NULL = entity-scoped AuthzEntityMembership)
- Rename default table names from buckets/files/upload_requests to app_buckets/app_files/app_upload_requests
- Add unique index on (database_id, COALESCE(membership_type, -1)) to enforce one module per scope
- Update entity_table_id comment to reflect app-level vs entity-scoped usage

Syncs with constructive-db PR #876 (merged).

Author: pyramation

packages/metaschema-modules/deploy/schemas/metaschema_modules_public/tables/storage_module/table.sql

@@ -18,11 +18,14 @@ CREATE TABLE metaschema_modules_public.storage_module (
     upload_requests_table_id uuid NOT NULL DEFAULT uuid_nil(),
 
     -- Table names (input to the generator)
-    buckets_table_name text NOT NULL DEFAULT 'buckets',
-    files_table_name text NOT NULL DEFAULT 'files',
-    upload_requests_table_name text NOT NULL DEFAULT 'upload_requests',
+    buckets_table_name text NOT NULL DEFAULT 'app_buckets',
+    files_table_name text NOT NULL DEFAULT 'app_files',
+    upload_requests_table_name text NOT NULL DEFAULT 'app_upload_requests',
 
-    -- Entity table for RLS (users table, since users and orgs share it)
+    -- Multi-tenant storage identity
+    membership_type int DEFAULT NULL,              -- NULL = global gate (AuthzMembership via app_sprt), non-NULL = entity-scoped (AuthzEntityMembership)
+
+    -- Entity table for RLS (NULL for app-level storage, entity table for entity-scoped storage)
     entity_table_id uuid NULL,
 
     -- S3 connection config (NULL = use global env/plugin defaults)
@@ -52,4 +55,8 @@ CREATE TABLE metaschema_modules_public.storage_module (
 
 CREATE INDEX storage_module_database_id_idx ON metaschema_modules_public.storage_module ( database_id );
 
+-- Unique constraint on (database_id, membership_type) using COALESCE to handle NULLs.
+-- NULL membership_type = app-level (only one per database), non-NULL = entity-scoped (one per membership_type per database).
+CREATE UNIQUE INDEX storage_module_unique_scope ON metaschema_modules_public.storage_module ( database_id, COALESCE(membership_type, -1) );
+
 COMMIT;