feat: interactive wizard approval

[okedeji]

Adds --interactive flag that shows the plan of events the wizard wants to implement, and then gets the user's approval before implementation. Without this, the wizard does not care if the suggested planned events are okay with the user, while irl the user may want to add more, remove some, or rename some.

How it works

1. Agent generates an event plan and outputs it between [WIZARD-APPROVAL-NEEDED] markers
2. User sees the plan and can Approve or Modify
3. If modified, the agent revises the plan and presents it again
4. This repeats until the user approves
5. Only then does the agent implement the approved events
6. If the flow errors unexpectedly, the agent emits [ERROR-APPROVAL-CANCELLED] and the wizard exits cleanly with no changes

Test plan

• pnpm build passes (including smoke test)
• pnpm jest — 132 passed, 0 failures
• Manual test: I ran with --interactive, modified the plan, verified that the updated plan was shown, then approved. Demo below. Check timestamp 00:07 to 00:35

PH.deo.mp4