feat: Add agent workspace system and runtime management

- Add agent core modules (agent_core, factory, registry, skill_loader)
- Add runtime system for agent execution management
- Add REST API for agents, workspaces, and runtime control
- Add process supervisor for agent lifecycle management
- Add workspace template system with agent profiles
- Add frontend RuntimeView and runtime API integration
- Add per-agent skill workspaces for smoke_fullstack run
- Refactor skill system with active/installed separation

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

runs/smoke_fullstack/agents/portfolio_manager/agent.yaml

@@ -0,0 +1,12 @@
+agent_id: portfolio_manager
+prompt_files:
+- SOUL.md
+- PROFILE.md
+- AGENTS.md
+- POLICY.md
+- MEMORY.md
+enabled_skills:
+- portfolio_decisioning
+disabled_skills: []
+active_tool_groups: []
+disabled_tool_groups: []