docs: fix CLI README to use correct command syntax

[roomote]

This PR corrects the CLI README to match the actual implementation.

What Changed

The CLI README was documenting incorrect syntax using -P flag for prompts. The actual implementation uses a positional argument for prompts, not a flag.

Fixes

• Updated all command examples to use correct syntax: roo "prompt" -w ~/workspace
• Fixed options table to show [prompt] as positional argument
• Added -w, --workspace flag documentation
• Removed references to non-existent -P, --prompt flag

Before

roo ~/project -P "What is this code?"  # WRONG

After

roo "What is this code?" -w ~/project  # CORRECT

This aligns the README with the actual implementation in index.ts.

---

Important

Fix CLI README to use correct command syntax with positional argument for prompts instead of -P flag.

• Behavior:
  • Corrects CLI README to use positional argument for prompts instead of -P flag.
  • Updates command examples to roo "prompt" -w ~/workspace.
  • Fixes options table to show [prompt] as positional argument.
• Documentation:
  • Adds -w, --workspace flag documentation.
  • Removes references to non-existent -P, --prompt flag.

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[roomote]

Rooviewer   See task on Roo Cloud

Review complete. No issues found.

The documentation changes correctly align the README with the actual CLI implementation. Verified that [prompt] is a positional argument and -w, --workspace is the workspace flag per apps/cli/src/index.ts.

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