test(storage): integration test for migrate-tier (FED-M1-08) + camelCase column fix (#477)

packages/storage/src/migrate-tier.ts

@@ -491,11 +491,24 @@ export class PostgresMigrationTarget implements MigrationTarget {
 /*  Source-row normalisation                                           */
 /* ------------------------------------------------------------------ */
 
+/**
+ * Convert a camelCase key to snake_case.
+ * e.g. "userId" → "user_id", "emailVerified" → "email_verified".
+ * Keys that are already snake_case (no uppercase letters) are returned as-is.
+ */
+function toSnakeCase(key: string): string {
+  return key.replace(/[A-Z]/g, (c) => `_${c.toLowerCase()}`);
+}
+
 /**
  * Drizzle returns rows as camelCase TypeScript objects (e.g. `userId`, not
  * `user_id`). The PostgresMigrationTarget upserts via raw SQL and uses the
- * column names as given — the `insights` no-vector path uses snake_case column
- * aliases in the SELECT, so those rows already arrive as snake_case.
+ * column names as given.  We must convert camelCase keys → snake_case before
+ * building the INSERT statement so column names match the PG schema.
+ *
+ * Exception: the `insights` no-vector path already returns snake_case keys
+ * from its raw SQL projection — toSnakeCase() is idempotent for already-
+ * snake_case keys so this conversion is safe in all paths.
  *
  * For vector tables (insights), if `embedding` is absent from the source row
  * (because DrizzleMigrationSource omitted it in the no-vector projection), we
@@ -509,7 +522,11 @@ export function normaliseSourceRow(
   row: Record<string, unknown>,
   sourceHasVector: boolean,
 ): Record<string, unknown> {
-  const out = { ...row };
+  // Convert all camelCase keys to snake_case for raw-SQL target compatibility.
+  const out: Record<string, unknown> = {};
+  for (const [k, v] of Object.entries(row)) {
+    out[toSnakeCase(k)] = v;
+  }
 
   if (VECTOR_TABLES.has(tableName) && !sourceHasVector) {
     // Source cannot have embeddings — explicitly null them so ON CONFLICT