refactor(backend): refactor project, add database migrations support

backend/alembic/versions/81f275275556_init_migration.py

@@ -0,0 +1,52 @@
+"""Init migration
+
+Revision ID: 81f275275556
+Revises: 
+Create Date: 2025-09-24 17:39:25.346690
+
+"""
+from typing import Sequence, Union
+
+import fastapi_users_db_sqlalchemy
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = '81f275275556'
+down_revision: Union[str, Sequence[str], None] = None
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('transaction',
+    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+    sa.Column('amount', sa.Float(), nullable=False),
+    sa.Column('description', sa.String(length=255), nullable=True),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_table('user',
+    sa.Column('first_name', sa.String(length=100), nullable=True),
+    sa.Column('last_name', sa.String(length=100), nullable=True),
+    sa.Column('id', fastapi_users_db_sqlalchemy.generics.GUID(), nullable=False),
+    sa.Column('email', sa.String(length=320), nullable=False),
+    sa.Column('hashed_password', sa.String(length=1024), nullable=False),
+    sa.Column('is_active', sa.Boolean(), nullable=False),
+    sa.Column('is_superuser', sa.Boolean(), nullable=False),
+    sa.Column('is_verified', sa.Boolean(), nullable=False),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_index(op.f('ix_user_email'), 'user', ['email'], unique=True)
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_index(op.f('ix_user_email'), table_name='user')
+    op.drop_table('user')
+    op.drop_table('transaction')
+    # ### end Alembic commands ###