Add listing decisions (like/dislike) backend with detail endpoint

- ListingDecision model with unique constraint on (user_id, listing_id, listing_type)
- Alembic migration for listingdecision table
- DecisionRepository with dialect-aware upsert (MySQL/SQLite)
- DecisionService with input validation
- Decision API routes: PUT/GET/DELETE on /api/decisions
- GET /api/listing/{id}/detail endpoint extracting full property info from additional_info
- Add listing ID to GeoJSON feature properties
- Decision filtering on GeoJSON stream endpoint (decision_filter param)

alembic/versions/d7e8f9a0b1c2_add_listing_decision.py

@@ -0,0 +1,49 @@
+"""add listing decision
+
+Revision ID: d7e8f9a0b1c2
+Revises: c5d6e7f8a9b0
+Create Date: 2026-02-21 12:00:00.000000
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+import sqlmodel
+
+
+# revision identifiers, used by Alembic.
+revision: str = 'd7e8f9a0b1c2'
+down_revision: Union[str, None] = 'c5d6e7f8a9b0'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Create listingdecision table."""
+    op.create_table('listingdecision',
+        sa.Column('id', sa.Integer(), nullable=False),
+        sa.Column('user_id', sa.Integer(), nullable=False),
+        sa.Column('listing_id', sa.Integer(), nullable=False),
+        sa.Column('listing_type', sqlmodel.sql.sqltypes.AutoString(), nullable=False),
+        sa.Column('decision', sqlmodel.sql.sqltypes.AutoString(), nullable=False),
+        sa.Column('created_at', sa.DateTime(), nullable=True,
+                  server_default=sa.func.now()),
+        sa.Column('updated_at', sa.DateTime(), nullable=True,
+                  server_default=sa.func.now()),
+        sa.ForeignKeyConstraint(['user_id'], ['user.id']),
+        sa.PrimaryKeyConstraint('id'),
+        sa.UniqueConstraint('user_id', 'listing_id', 'listing_type',
+                            name='uq_decision_user_listing_type'),
+    )
+    op.create_index(op.f('ix_listingdecision_user_id'),
+                    'listingdecision', ['user_id'], unique=False)
+    op.create_index(op.f('ix_listingdecision_listing_id'),
+                    'listingdecision', ['listing_id'], unique=False)
+
+
+def downgrade() -> None:
+    """Drop listingdecision table."""
+    op.drop_index(op.f('ix_listingdecision_listing_id'), table_name='listingdecision')
+    op.drop_index(op.f('ix_listingdecision_user_id'), table_name='listingdecision')
+    op.drop_table('listingdecision')