feat: add config profiles data model and migrations

- Add ConfigProfile model with user ownership, name, description
- Add ConfigInclude model for ordered profile self-references
- Add ConfigMount model for mount/file definitions
- Add selected_profile_id to ToolInstance for per-instance profile selection
- Add default profile properties to UserConfig JSONB config
- Create Alembic migration 0013 for new tables and columns
- Register new models in models/__init__.py
- Mark config_folders.is_active as deprecated
- Add migration metadata test

Quality gates: syntax check passed (all files parse successfully)
OpenSpec: add-config-profiles task 1.1

apps/api/src/models/tool_instance.py

@@ -9,6 +9,7 @@ from sqlalchemy.orm import Mapped, mapped_column, relationship
 from src.models.base import Base, TimestampMixin, UUIDPrimaryKeyMixin
 
 if TYPE_CHECKING:
+    from src.models.config_profile import ConfigProfile
     from src.models.git_repository import GitRepository
     from src.models.project import Project
     from src.models.tool_type import ToolType
@@ -62,8 +63,12 @@ class ToolInstance(UUIDPrimaryKeyMixin, TimestampMixin, Base):
     last_stopped_at: Mapped[datetime | None] = mapped_column(
         DateTime(timezone=True), nullable=True
     )
+    selected_profile_id: Mapped[uuid.UUID | None] = mapped_column(
+        UUID(), ForeignKey("config_profiles.id", ondelete="SET NULL"), nullable=True
+    )
 
     tool_type: Mapped["ToolType"] = relationship()
     repository: Mapped["GitRepository"] = relationship()
     project: Mapped["Project"] = relationship()
     owner: Mapped["User"] = relationship()
+    selected_profile: Mapped["ConfigProfile | None"] = relationship()