feat: step 7's migration, with an index on spaceId

The first migration since the initial one, created with the CLI (serverpod create-migration --tag studysets), since no MCP bridge was set up yet. On the server it is one transaction that only adds: gen_random_uuid_v7(), the studyset table, the sync engine's tables (spaces, their members and nodes, the CRDT bookkeeping, the log of integrity violations) with their foreign keys, and, from Serverpod v4.0.3, the auth module's profile image foreign key re-created as DEFERRABLE INITIALLY DEFERRED, so that dumps restore. The server tests apply it to their Postgres.

studyset gets an index on spaceId: deleting a space cascades into every synced table, and Postgres doesn't index foreign keys by itself, so account deletion and pruning would otherwise read whole tables. AGENTS.md makes it the rule for every synced table.

The client migration creates each device's SQLite schema. The generator builds it from the whole definition, so it also contains the server's own tables; only the synced tables and the bookkeeping ever hold data on a device.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

halkyon_learn_client/lib/migrations/20260930094729362-studysets/definition_project.json

@@ -0,0 +1,113 @@
+{
+  "__className__": "serverpod.DatabaseDefinition",
+  "schemaVersion": 2,
+  "moduleName": "halkyon_learn",
+  "tables": [
+    {
+      "__className__": "serverpod.TableDefinition",
+      "name": "studyset",
+      "dartName": "Studyset",
+      "module": "halkyon_learn",
+      "schema": "public",
+      "columns": [
+        {
+          "__className__": "serverpod.ColumnDefinition",
+          "name": "id",
+          "fieldName": "id",
+          "columnType": 7,
+          "isNullable": false,
+          "columnDefault": "random_v7",
+          "dartType": "UuidValue?"
+        },
+        {
+          "__className__": "serverpod.ColumnDefinition",
+          "name": "spaceId",
+          "fieldName": "spaceId",
+          "columnType": 6,
+          "isNullable": true,
+          "dartType": "int?"
+        },
+        {
+          "__className__": "serverpod.ColumnDefinition",
+          "name": "keyId",
+          "fieldName": "keyId",
+          "columnType": 0,
+          "isNullable": true,
+          "dartType": "String?"
+        },
+        {
+          "__className__": "serverpod.ColumnDefinition",
+          "name": "payload",
+          "fieldName": "payload",
+          "columnType": 5,
+          "isNullable": false,
+          "dartType": "dart:typed_data:ByteData"
+        },
+        {
+          "__className__": "serverpod.ColumnDefinition",
+          "name": "nonce",
+          "fieldName": "nonce",
+          "columnType": 5,
+          "isNullable": true,
+          "dartType": "dart:typed_data:ByteData?"
+        }
+      ],
+      "foreignKeys": [
+        {
+          "__className__": "serverpod.ForeignKeyDefinition",
+          "constraintName": "studyset_fk_0",
+          "columns": [
+            "spaceId"
+          ],
+          "referenceTable": "offline_sync_spaces",
+          "referenceTableSchema": "public",
+          "referenceColumns": [
+            "id"
+          ],
+          "onUpdate": 3,
+          "onDelete": 4
+        }
+      ],
+      "indexes": [
+        {
+          "__className__": "serverpod.IndexDefinition",
+          "indexName": "studyset_space_idx",
+          "elements": [
+            {
+              "__className__": "serverpod.IndexElementDefinition",
+              "type": 0,
+              "definition": "spaceId"
+            }
+          ],
+          "type": "btree",
+          "isUnique": false,
+          "isPrimary": false
+        }
+      ],
+      "managed": true
+    }
+  ],
+  "installedModules": [
+    {
+      "__className__": "serverpod.DatabaseMigrationVersion",
+      "module": "serverpod",
+      "version": "20260824182259319"
+    },
+    {
+      "__className__": "serverpod.DatabaseMigrationVersion",
+      "module": "serverpod_auth_idp",
+      "version": "20260924105404509"
+    },
+    {
+      "__className__": "serverpod.DatabaseMigrationVersion",
+      "module": "serverpod_offline_sync",
+      "version": "20260914143806119"
+    },
+    {
+      "__className__": "serverpod.DatabaseMigrationVersion",
+      "module": "serverpod_auth_core",
+      "version": "20260924105232991"
+    }
+  ],
+  "migrationApiVersion": 1
+}

halkyon_learn_client/lib/migrations/migration_registry.dart

@@ -1,15 +1,18 @@
-/// AUTOGENERATED BY SERVERPOD generate - do not remove.
-/// Merging: resolve conflicts like server migration_registry.txt.
-/// Updated when you run `serverpod create-migration` for the client.
+/// AUTOGENERATED BY SERVERPOD create-migration - DO NOT EDIT BY HAND
+/// Merging: resolve registry conflicts the same as migration_registry.txt.
 library;
 
 import 'package:serverpod_database/serverpod_database.dart';
 
+part '20260930094729362-studysets/migration.dart';
+
 /// Migration registry for the client-side database.
 class MigrationRegistry {
   /// Ordered list of all client-side database migrations.
   /// New migrations are always appended at the end.
-  static final List<MigrationVersionSql> migrations = [];
+  static final List<MigrationVersionSql> migrations = [
+    _Migration20260930094729362_studysets(),
+  ];
 
   /// List of all client-side database migration versions.
   static List<String> get versions => migrations.map((m) => m.version).toList();

halkyon_learn_client/lib/src/protocol/protocol.dart

@@ -88,7 +88,21 @@ class Protocol extends _isd.DatabaseSerializationManager {
           matchType: null,
         ),
       ],
-      indexes: [],
+      indexes: [
+        _isd.IndexDefinition(
+          indexName: 'studyset_space_idx',
+          tableSpace: null,
+          elements: [
+            _isd.IndexElementDefinition(
+              type: _isd.IndexElementDefinitionType.column,
+              definition: 'spaceId',
+            ),
+          ],
+          type: 'btree',
+          isUnique: false,
+          isPrimary: false,
+        ),
+      ],
       managed: true,
     ),
     ..._iaic.Protocol() is _isd.DatabaseSerializationManager