feat: add link_type field to quick links

Adds link_type column to quick_links table for iframe vs new_tab behavior.
Includes Alembic migration and schema updates.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

alembic/versions/20260103_1314_f0349c95aa5d_add_link_type_to_quick_links.py

@@ -0,0 +1,26 @@
+"""add_link_type_to_quick_links
+
+Revision ID: f0349c95aa5d
+Revises: 003
+Create Date: 2026-01-03 13:14:46.911770+00:00
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+# revision identifiers, used by Alembic.
+revision: str = 'f0349c95aa5d'
+down_revision: Union[str, None] = '003'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    op.add_column('quick_links', sa.Column('link_type', sa.String(length=20), nullable=True, server_default='iframe'))
+    # Update existing rows to have the default value
+    op.execute("UPDATE quick_links SET link_type = 'iframe' WHERE link_type IS NULL")
+
+
+def downgrade() -> None:
+    op.drop_column('quick_links', 'link_type')