test(cli): stabilize prompt cancellation waits

[markijbema]

Summary

• Replace several infinite fake LLM streams in prompt cancellation tests with gated finite streams.
• Wait for shell busy state through SessionStatus instead of fixed startup sleeps in active shell queue tests.
• Keep remaining process/assertion-window sleeps unchanged to limit the first PR scope.

Notes

• bun run script/check-opencode-annotations.ts passed.
• bun test ./test/session/prompt.test.ts could not run locally because @opentui/solid/preload is missing in this workspace.
• bun run typecheck could not run locally because tsgo is missing in this workspace.

[kilo-code-bot]

Code Review Summary

Status: No Issues Found | Recommendation: Merge

Files Reviewed (1 files)

• packages/opencode/test/session/prompt.test.ts

---

_{Reviewed by gpt-5.5-20260423 · 272,860 tokens}