feat: set hatchet as default for multitracks (#822)

* set hatchet as default for multitracks

* fix: pipeline routing tests for hatchet-default branch

- Create room with use_celery=True to force Celery backend in tests
- Link transcript to room to enable multitrack pipeline routing
- Fixes test failures caused by missing HATCHET_CLIENT_TOKEN in test env

* Update server/reflector/services/transcript_process.py

Co-authored-by: pr-agent-monadical[bot] <198624643+pr-agent-monadical[bot]@users.noreply.github.com>

---------

Co-authored-by: Igor Loskutov <igor.loskutoff@gmail.com>
Co-authored-by: pr-agent-monadical[bot] <198624643+pr-agent-monadical[bot]@users.noreply.github.com>

server/migrations/versions/80beb1ea3269_replace_use_hatchet_with_use_celery.py

@@ -0,0 +1,44 @@
+"""replace_use_hatchet_with_use_celery
+
+Revision ID: 80beb1ea3269
+Revises: bd3a729bb379
+Create Date: 2026-01-20 16:26:25.555869
+
+"""
+
+from typing import Sequence, Union
+
+import sqlalchemy as sa
+from alembic import op
+
+# revision identifiers, used by Alembic.
+revision: str = "80beb1ea3269"
+down_revision: Union[str, None] = "bd3a729bb379"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    with op.batch_alter_table("room", schema=None) as batch_op:
+        batch_op.add_column(
+            sa.Column(
+                "use_celery",
+                sa.Boolean(),
+                server_default=sa.text("false"),
+                nullable=False,
+            )
+        )
+        batch_op.drop_column("use_hatchet")
+
+
+def downgrade() -> None:
+    with op.batch_alter_table("room", schema=None) as batch_op:
+        batch_op.add_column(
+            sa.Column(
+                "use_hatchet",
+                sa.Boolean(),
+                server_default=sa.text("false"),
+                nullable=False,
+            )
+        )
+        batch_op.drop_column("use_celery")