Shorten alembic revision ids to fit version_num VARCHAR(32)

The deploy's `alembic upgrade head` failed at 016->017 with
StringDataRightTruncationError: the revision id
"017_add_trade_setup_strategy_rank" is 33 chars, but Postgres's
alembic_version.version_num is VARCHAR(32). Offline/SQLite checks don't
enforce the length, so this only surfaced against prod Postgres.

Rename the revision ids to the repo's short numeric convention (017, 018);
descriptive filenames are kept. down_revision links updated to match.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

alembic/versions/017_add_trade_setup_strategy_rank.py

@@ -1,6 +1,6 @@
 """Add production strategy rank fields to trade setups.
 
-Revision ID: 017_add_trade_setup_strategy_rank
+Revision ID: 017
 Revises: 016
 Create Date: 2026-07-03 20:15:00.000000
 """
@@ -11,7 +11,7 @@ from alembic import op
 import sqlalchemy as sa
 
 
-revision = "017_add_trade_setup_strategy_rank"
+revision = "017"
 down_revision = "016"
 branch_labels = None
 depends_on = None