Fix: use Windows-compatible agent launcher commands

[guuido]

Summary

• Fixes terminal agent launcher commands on Windows.
• Updates Claude, Codex, and Copilot launch buttons to use Windows-compatible environment variable syntax.
• Keeps existing behavior unchanged on macOS and Linux.

Root Cause

• The launcher used POSIX inline environment syntax (READO_AGENT=... command).
• In Windows cmd, that syntax is invalid and gets interpreted as an unknown command.

Changes

• Added Windows detection in terminal launcher logic.
• Added a helper to build the correct command per OS:
  • Windows: set "READO_AGENT=<agent>" && <bin>
  • Unix-like: READO_AGENT=<agent> <bin>
• Updated all three agent launch buttons to use the helper.

Summary by CodeRabbit

• Bug Fixes
  • Fixed agent launcher behavior so the generated launch commands render and execute correctly on both Windows and non-Windows platforms.
• New Features
  • Added support for retrieving the default shell for newly spawned PTY sessions, enabling more accurate, shell-aware agent startup from the terminal UI.

[coderabbitai]

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ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 54f63412-211a-435e-bdd6-7d8d1f67e46c

📥 Commits

Reviewing files that changed from the base of the PR and between 0dc3d01 and 5e2ac55.

📒 Files selected for processing (1)

• src/components/organisms/TerminalPanel.tsx

📝 Walkthrough

Walkthrough

The backend PTY system now exposes its default shell via a new pty_default_shell Tauri command, which is wrapped in the frontend API as ptyDefaultShell(). TerminalPanel uses this to detect the active shell and OS, then defines agentLaunchCommand(agent, bin) to generate OS-specific command syntax: set "READO_AGENT=..." && bin on Windows or READO_AGENT=... bin elsewhere, with additional PowerShell-specific handling. All three agent launcher buttons (Claude Code, Codex, Copilot) are updated to call this helper instead of using hardcoded command strings.

Changes

Shell-aware agent launch command

Layer / File(s)	Summary
Backend PTY shell exposure src-tauri/src/pty.rs, src-tauri/src/lib.rs	New pty_default_shell() Tauri command exposes the default shell executable path from the PTY subsystem and is registered in the invoke handler.
Frontend PTY shell API wrapper src/lib/api.ts	New ptyDefaultShell() export wraps the backend command and returns a Promise that resolves to the shell name string.
Terminal shell-aware launch command and launcher buttons src/components/organisms/TerminalPanel.tsx	Imports ptyDefaultShell and populates a defaultShell state; detects Windows OS and PowerShell via navigator.userAgent and shell name; defines agentLaunchCommand(agent, bin) that emits set "READO_AGENT=..." && bin on Windows or READO_AGENT=... bin elsewhere; updates Claude Code, Codex, and Copilot launcher button onClick handlers to call this helper instead of hardcoded strings.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

Poem

A bunny crafts shells with care,
Backend whispers which one's there.
Windows gets set, the rest align,
Now every agent runs just fine!
🐇 ✨

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely summarizes the main change: implementing Windows-compatible agent launcher commands by detecting the OS and generating platform-specific command syntax.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/windows-agent-launch

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@src/components/organisms/TerminalPanel.tsx`:
- Around line 95-98: The agentLaunchCommand function generates Windows shell
commands using cmd.exe syntax (set command) which fails on PowerShell since set
is not a recognized PowerShell command. Update the agentLaunchCommand helper to
detect whether the shell is PowerShell or cmd.exe (you can check the COMSPEC
environment variable or shell type), and generate the appropriate syntax: use
set "READO_AGENT=..." && ... for cmd.exe, and use $env:READO_AGENT="..."; ...
for PowerShell. Alternatively, pass the agent name through a method that works
universally across both shells instead of relying on environment variable
syntax.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 70631024-de18-49cd-a99d-743a5cf1c4b8

📥 Commits

Reviewing files that changed from the base of the PR and between eb44029 and 022547d.

📒 Files selected for processing (1)

• src/components/organisms/TerminalPanel.tsx