feat(db): add sqlx migrate feature and renumber migration files

- Add 'migrate' feature to sqlx dependency
- Renumber migrations to fix duplicate version numbers (two 014 files)
- Re-sequence migrations 009-012 for continuous ordering
- Add ALTER TABLE ADD COLUMN IF NOT EXISTS baseline for notification
  table to handle existing databases missing newer columns
- Remove deleted IM migration files (009-012) that were superseded

migrate/010_add_deleted_at_user_tables.sql

@@ -0,0 +1,24 @@
+-- Add deleted_at columns to user-related tables for soft-delete support.
+-- Previously, user_delete_account hard-deleted rows from these tables.
+-- After this migration, all deletions are soft (mark as deleted).
+
+ALTER TABLE "user" ADD COLUMN IF NOT EXISTS restore_token_hash VARCHAR(64);
+ALTER TABLE "user" ADD COLUMN IF NOT EXISTS restore_token_expires_at TIMESTAMPTZ;
+
+ALTER TABLE user_2fa ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMPTZ;
+ALTER TABLE user_activity ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMPTZ;
+ALTER TABLE user_appearance ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMPTZ;
+ALTER TABLE user_block ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMPTZ;
+ALTER TABLE user_device ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMPTZ;
+ALTER TABLE user_follow ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMPTZ;
+ALTER TABLE user_mail ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMPTZ;
+ALTER TABLE user_notify_setting ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMPTZ;
+ALTER TABLE user_oauth ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMPTZ;
+ALTER TABLE user_password ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMPTZ;
+ALTER TABLE user_password_reset ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMPTZ;
+ALTER TABLE user_presence ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMPTZ;
+ALTER TABLE user_profile ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMPTZ;
+ALTER TABLE user_security_log ADD COLUMN IF NOT EXISTS deleted_at TIMESTAMPTZ;
+
+CREATE INDEX IF NOT EXISTS idx_user_security_log_user_deleted ON user_security_log(user_id, deleted_at);
+CREATE INDEX IF NOT EXISTS idx_user_activity_user_deleted ON user_activity(user_id, deleted_at);