fix(api): make alembic migrations idempotent for fresh databases

- 001: guard has_table check; skip if session_data already TEXT
- 002: guard each ADD COLUMN / CREATE TABLE; guard password migration
- 003: guard has_table; guard nullable check
- 004: guard has_table; skip if users.id already TEXT
- env.py: add Base.metadata.create_all after run_migrations to bootstrap fresh DBs
- api/user.py: make hashed_password nullable; add email_verified, image, email_inbound_token fields

Co-Authored-By: Paperclip <noreply@paperclip.ing>

alembic/versions/004_fix_user_id_text.py

@@ -25,7 +25,21 @@ depends_on = None
 
 
 def upgrade() -> None:
-    # Step 1: Drop existing FK constraints
+    conn = op.get_bind()
+    inspector = sa.inspect(conn)
+
+    # Fresh DB — no tables yet, nothing to convert
+    if not inspector.has_table("users"):
+        return
+
+    # Check if already TEXT (Base.metadata.create_all uses TEXT for fresh DB)
+    users_cols = {c["name"]: c for c in inspector.get_columns("users")}
+    if "id" in users_cols:
+        id_type = str(users_cols["id"]["type"]).lower()
+        if "text" in id_type and "uuid" not in id_type:
+            return  # already TEXT — nothing to do
+
+    # Step 1: Drop existing FK constraints (ignore if they don't exist)
     op.execute(text("ALTER TABLE user_store_accounts DROP CONSTRAINT IF EXISTS user_store_accounts_user_id_fkey"))
     op.execute(text("ALTER TABLE purchases DROP CONSTRAINT IF EXISTS purchases_user_id_fkey"))