feat: add multi-dialect schema initialization

src/core/errors.ts

@@ -0,0 +1,13 @@
+export class IdentityDBError extends Error {
+  constructor(message: string) {
+    super(message);
+    this.name = 'IdentityDBError';
+  }
+}
+
+export class IdentityDBConfigurationError extends IdentityDBError {
+  constructor(message: string) {
+    super(message);
+    this.name = 'IdentityDBConfigurationError';
+  }
+}

src/core/migrations.ts

@@ -0,0 +1,68 @@
+import type { Kysely } from 'kysely';
+
+import {
+  FACTS_TABLE,
+  FACT_TOPICS_TABLE,
+  TOPICS_TABLE,
+} from './schema';
+import type { IdentityDatabaseSchema } from '../types/database';
+
+export async function initializeSchema(
+  db: Kysely<IdentityDatabaseSchema>,
+): Promise<void> {
+  await db.schema
+    .createTable(TOPICS_TABLE)
+    .ifNotExists()
+    .addColumn('id', 'text', (column) => column.primaryKey())
+    .addColumn('name', 'text', (column) => column.notNull())
+    .addColumn('normalized_name', 'text', (column) => column.notNull().unique())
+    .addColumn('category', 'text', (column) => column.notNull())
+    .addColumn('granularity', 'text', (column) => column.notNull())
+    .addColumn('description', 'text')
+    .addColumn('metadata', 'text')
+    .addColumn('created_at', 'text', (column) => column.notNull())
+    .addColumn('updated_at', 'text', (column) => column.notNull())
+    .execute();
+
+  await db.schema
+    .createTable(FACTS_TABLE)
+    .ifNotExists()
+    .addColumn('id', 'text', (column) => column.primaryKey())
+    .addColumn('statement', 'text', (column) => column.notNull())
+    .addColumn('summary', 'text')
+    .addColumn('source', 'text')
+    .addColumn('confidence', 'real')
+    .addColumn('metadata', 'text')
+    .addColumn('created_at', 'text', (column) => column.notNull())
+    .addColumn('updated_at', 'text', (column) => column.notNull())
+    .execute();
+
+  await db.schema
+    .createTable(FACT_TOPICS_TABLE)
+    .ifNotExists()
+    .addColumn('fact_id', 'text', (column) =>
+      column.notNull().references(`${FACTS_TABLE}.id`).onDelete('cascade'),
+    )
+    .addColumn('topic_id', 'text', (column) =>
+      column.notNull().references(`${TOPICS_TABLE}.id`).onDelete('cascade'),
+    )
+    .addColumn('role', 'text')
+    .addColumn('position', 'integer', (column) => column.notNull())
+    .addColumn('created_at', 'text', (column) => column.notNull())
+    .addPrimaryKeyConstraint('fact_topics_pk', ['fact_id', 'topic_id', 'position'])
+    .execute();
+
+  await db.schema
+    .createIndex('fact_topics_topic_id_idx')
+    .ifNotExists()
+    .on(FACT_TOPICS_TABLE)
+    .column('topic_id')
+    .execute();
+
+  await db.schema
+    .createIndex('fact_topics_fact_id_idx')
+    .ifNotExists()
+    .on(FACT_TOPICS_TABLE)
+    .column('fact_id')
+    .execute();
+}