fix: resolve alembic migration cycle — unique revision ID, correct chain

The previous migration used revision 'a1b2c3d4e5f6' which was already
taken by 005_add_reset_token_to_users.py, causing a cycle. Also both
f6a7b8c9d0e1 and the new migration pointed to the same down_revision.

Fixed:
- New unique revision ID: b7c8d9e0f1a2
- down_revision points to f6a7b8c9d0e1 (current head)
- Chain: e5b2c9d1f4a8 → f6a7b8c9d0e1 → b7c8d9e0f1a2

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

alembic/versions/b7c8d9e0f1a2_set_multilingual_target_language.py

@@ -1,7 +1,7 @@
 """Set multilingual glossaries target_language to 'multi'
 
-Revision ID: a1b2c3d4e5f6
-Revises: e5b2c9d1f4a8
+Revision ID: b7c8d9e0f1a2
+Revises: f6a7b8c9d0e1
 Create Date: 2026-05-31
 
 Glossary templates that were enriched with multilingual translations
@@ -19,8 +19,8 @@ from alembic import op
 import sqlalchemy as sa
 
 # revision identifiers
-revision = "a1b2c3d4e5f6"
-down_revision = "e5b2c9d1f4a8"
+revision = "b7c8d9e0f1a2"
+down_revision = "f6a7b8c9d0e1"
 branch_labels: Union[str, Sequence[str], None] = None
 depends_on: Union[str, Sequence[str], None] = None