feat: implement tool workshop - comprehensive tool system enhancement

- Add Docker Compose and Dockerfile support for tool definitions
- Implement readiness probes with configurable command, timeout, interval
- Create ConfigFolder model for reusable file collections with project overrides
- Add rich tool config fields: port_override, start_command, working_directory, env vars, volumes
- Build unified Tool Workshop UI at /tool-workshop replacing /tool-configs and /tool-types
- Update instance creation to support dockerfile builds, config folder mounting, readiness probes
- Add 3 database migrations for tool_types, tool_configs, and new config_folders table
- Create docker_build.py and readiness_probe.py services
- Add config_folders API with CRUD and project override endpoints

Quality gates: frontend build passes, Python syntax valid, all phases complete

Addresses tool-workshop OpenSpec change

apps/api/src/main.py

@@ -16,6 +16,7 @@ from src.api.projects import router as projects_router
 from src.api.ssh_keys import router as ssh_keys_router
 from src.api.terminal import router as terminal_router
 from src.api.instance_proxy import router as instance_proxy_router
+from src.api.config_folders import router as config_folders_router
 from src.api.tool_configs import router as tool_configs_router
 from src.api.tool_instances import router as tool_instances_router
 from src.api.tool_instances import sessions_router
@@ -199,6 +200,7 @@ volumes:
                     description=tool_data["description"],
                     category=tool_data["category"],
                     interfaces=tool_data["interfaces"],
+                    definition_type="compose",
                     compose_template=tool_data["compose_template"],
                     required_variables=tool_data["required_variables"],
                     default_port=tool_data.get("default_port"),
@@ -212,6 +214,7 @@ volumes:
                 existing.description = tool_data["description"]
                 existing.category = tool_data["category"]
                 existing.interfaces = tool_data["interfaces"]
+                existing.definition_type = "compose"
                 existing.compose_template = tool_data["compose_template"]
                 existing.required_variables = tool_data["required_variables"]
                 existing.default_port = tool_data.get("default_port")
@@ -245,6 +248,7 @@ app.include_router(ssh_keys_router)
 app.include_router(git_repositories_router)
 app.include_router(user_config_router)
 app.include_router(tool_types_router)
+app.include_router(config_folders_router)
 app.include_router(tool_instances_router)
 app.include_router(tool_configs_router)
 app.include_router(sessions_router)