Implement CLI commands (add, list, done, remove)

[sharpHL]

Goal

Wire up the CLI argument parser and connect to the storage module.

Acceptance Criteria

• task add "text" — adds a new task
• task list — shows all tasks with status
• task done <id> — marks task as complete
• task remove <id> — deletes a task
• Helpful error messages for invalid input
• Unit tests for argument parsing

Technical Notes

• Use process.argv directly, no external deps
• Depends on Issue Implement task storage module #1 (storage module) ✅ merged

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Status: 🟢 Complete — PR pending

Current Context

• Branch: feat/2-cli-commands
• Last session: 2026-03-03 17:50 GMT+8
• Working on: Done, awaiting PR merge

Completed

• src/cli.js — full CLI with add, list, done, remove, help commands
• src/cli.test.js — 13 tests, all passing
• Error handling for missing args, invalid IDs, unknown commands
• All 22 tests pass (store + cli combined)

Decisions Made

• No external arg parser — process.argv.slice(2) + switch is sufficient for 4 commands
• done command toggles (not just marks done) — more useful for correcting mistakes
• Checkmark ✓ in list output for visual clarity

Gotchas

• None

Next Session Start Here

• PR ready for merge. After merge, Issue Add search command with keyword filtering #3 (search command) can start.