fix(plan): skip auto-execute when run --plan produces a direct answer

[zjshen14]

Summary

• opencli run --plan was unconditionally replaying the plan text back into a react-mode agent pass, even when the plan-mode pass had already produced a complete informational answer (no steps to execute)
• Adds a looksLikeActionablePlan guard that checks for numbered steps (1.), step headings (Step N:), or plan/steps section headers (## Plan, ## Steps) — only text matching these patterns triggers auto-execution
• Direct prose answers (e.g. "The file has 11 lines.") are treated as final responses and not re-executed, avoiding the confusing "I need a plan. Please provide the steps you'd like me to take." response

Closes #125

Test plan

• npm run typecheck && npm run lint && npm run format:check && npm test — all pass (531 tests, 10 new)
• New unit tests in src/cli/plan.test.ts cover: numbered steps → actionable, indented numbered steps → actionable, ## Plan header → actionable, ## Steps header → actionable, # Steps → actionable, Step N: heading → actionable, plain informational answer → not actionable, single-sentence answer → not actionable, empty string → not actionable, prose without step markers → not actionable
• Manual: opencli run "List files in src/ and tell me how many lines src/math.ts has." --plan --yes → plan answer printed, no "Executing plan…" follow-up
• Manual: opencli run "Add a divide(a,b) function to src/math.ts" --plan --yes → numbered plan printed, then "Executing plan…" and execution proceeds

Co-Authored-By: Claude Sonnet 4.6 noreply@anthropic.com

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Generated by Claude Code

[zjshen14]

Clean fix for a real problem. The looksLikeActionablePlan heuristic is appropriately conservative — it prefers false negatives (skip execution of a real plan; user re-runs if needed) over blindly routing everything through an execute pass. The 10 test cases cover the important positive and negative examples.

One edge case to be aware of: an informational answer that happens to include a numbered list. For example:

There are three main config locations:
1. ~/.opencli/config.json — global settings
2. .opencli/settings.json — project settings
3. .env — API keys

This matches /^\s*\d+\./m and would be treated as an actionable plan, triggering an unnecessary execute pass. The execute pass would likely produce no tool calls and exit cleanly, so the cost is an extra LLM round-trip rather than a broken execution — which is much better than the pre-fix behavior (routing all prose through execute). The heuristic is reasonable at this granularity.

If false positives become noisy in practice, requiring both a numbered step AND an imperative verb at the start of the step (e.g. /^\s*\d+\.\s+[A-Z][a-z]+/m) could tighten it, but that's an optimization for later.

Recommendation: merge. The status quo (every response routed through execute) is worse than this heuristic's occasional false positive.

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Generated by Claude Code