feat(tool-config): add categories, interfaces, and config management

Add support for tool categories, interface types, and per-tool configuration.

Backend:
- Add category and interfaces fields to ToolType model
- Create ToolConfig model for storing tool-specific settings
- Add tool_configs API endpoints (CRUD)
- Update built-in tool types with categories and interfaces:
  - code-server: editor, [web]
  - jupyter-notebook: notebook, [web]
  - opencode: ai-assistant, [terminal]
- Update instance API to include tool type interfaces
- Create Alembic migrations 0008 and 0009

Frontend:
- Update ToolType and Session interfaces with new fields
- Conditionally show Open/Terminal buttons based on tool interfaces
- Add API client for tool configs

OpenSpec: tool-config-management change created and implemented.

apps/api/alembic/versions/0008_tool_type_category.py

@@ -0,0 +1,33 @@
+"""add category and interfaces to tool_types
+
+Revision ID: 0008_tool_type_category
+Revises: 0007_instance_container_name
+Create Date: 2026-05-20 09:00:00.000000
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+# revision identifiers, used by Alembic.
+revision: str = "0008_tool_type_category"
+down_revision: Union[str, None] = "0007_instance_container_name"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    op.add_column(
+        "tool_types",
+        sa.Column("category", sa.String(50), nullable=False, server_default="other")
+    )
+    op.add_column(
+        "tool_types",
+        sa.Column("interfaces", sa.JSON(), nullable=False, server_default='["web"]')
+    )
+
+
+def downgrade() -> None:
+    op.drop_column("tool_types", "interfaces")
+    op.drop_column("tool_types", "category")

apps/api/alembic/versions/0009_tool_configs.py

@@ -0,0 +1,46 @@
+"""add tool_configs table
+
+Revision ID: 0009_tool_configs
+Revises: 0008_tool_type_category
+Create Date: 2026-05-20 09:00:00.000000
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects import postgresql
+
+# revision identifiers, used by Alembic.
+revision: str = "0009_tool_configs"
+down_revision: Union[str, None] = "0008_tool_type_category"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    op.create_table(
+        "tool_configs",
+        sa.Column("id", postgresql.UUID(as_uuid=True), server_default=sa.text("gen_random_uuid()"), nullable=False),
+        sa.Column("user_id", postgresql.UUID(as_uuid=True), nullable=False),
+        sa.Column("tool_type_id", postgresql.UUID(as_uuid=True), nullable=False),
+        sa.Column("project_id", postgresql.UUID(as_uuid=True), nullable=True),
+        sa.Column("key", sa.String(255), nullable=False),
+        sa.Column("value", sa.Text(), nullable=False),
+        sa.Column("config_type", sa.String(20), nullable=False, server_default="env"),
+        sa.Column("file_path", sa.String(1024), nullable=True),
+        sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.text("now()"), nullable=False),
+        sa.Column("updated_at", sa.DateTime(timezone=True), server_default=sa.text("now()"), nullable=False),
+        sa.ForeignKeyConstraint(["user_id"], ["users.id"]),
+        sa.ForeignKeyConstraint(["tool_type_id"], ["tool_types.id"]),
+        sa.ForeignKeyConstraint(["project_id"], ["projects.id"]),
+        sa.PrimaryKeyConstraint("id"),
+    )
+    op.create_index("idx_tool_configs_user_tool", "tool_configs", ["user_id", "tool_type_id"])
+    op.create_index("idx_tool_configs_project", "tool_configs", ["project_id"])
+
+
+def downgrade() -> None:
+    op.drop_index("idx_tool_configs_project", table_name="tool_configs")
+    op.drop_index("idx_tool_configs_user_tool", table_name="tool_configs")
+    op.drop_table("tool_configs")