[WIP] Incorporate inner and speculative arcs into ArcInfo and allocator API and other changes:

[mariakleiner]

• Arc::instantiate doesn’t take recipe anymore (just particle and handles)
• move almost all inner arcs logic outside Arc (only idle still there)
• refactor cloneForSpeculativeExecution method
• refactor speculator to support no particle instantiation mode
• remove unused methods from arc.ts and suggestion.ts