fix: add missing timestamps to ssh_keys model

SSHKey model was missing created_at/updated_at columns which the API
response model expected. Add TimestampMixin and Alembic migration.

apps/api/alembic/versions/0005_ssh_keys_timestamps.py

@@ -0,0 +1,44 @@
+"""add timestamps to ssh_keys table
+
+Revision ID: 0005_ssh_keys_timestamps
+Revises: 0004_tool_types
+Create Date: 2026-05-19 09:00:00.000000
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = "0005_ssh_keys_timestamps"
+down_revision: Union[str, None] = "0004_tool_types"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    op.add_column(
+        "ssh_keys",
+        sa.Column(
+            "created_at",
+            sa.DateTime(timezone=True),
+            server_default=sa.text("now()"),
+            nullable=True,
+        ),
+    )
+    op.add_column(
+        "ssh_keys",
+        sa.Column(
+            "updated_at",
+            sa.DateTime(timezone=True),
+            server_default=sa.text("now()"),
+            nullable=True,
+        ),
+    )
+
+
+def downgrade() -> None:
+    op.drop_column("ssh_keys", "updated_at")
+    op.drop_column("ssh_keys", "created_at")

apps/api/src/models/ssh_key.py

@@ -5,14 +5,14 @@ from sqlalchemy import ForeignKey, String, Text
 from sqlalchemy import Uuid as UUID
 from sqlalchemy.orm import Mapped, mapped_column, relationship
 
-from src.models.base import Base, UUIDPrimaryKeyMixin
+from src.models.base import Base, TimestampMixin, UUIDPrimaryKeyMixin
 
 if TYPE_CHECKING:
     from src.models.project import Project
     from src.models.user import User
 
 
-class SSHKey(UUIDPrimaryKeyMixin, Base):
+class SSHKey(UUIDPrimaryKeyMixin, TimestampMixin, Base):
     __tablename__ = "ssh_keys"
 
     name: Mapped[str] = mapped_column(String(255))