Fix trace command on Windows project drives

[emulatronicGIT]

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[emulatronicGIT]

Fixes #48.

What changed

• Build the trace command without wrapping it in a shell-level cd ...; ... command.
• Keep using the selected project directory as the child process cwd.
• Add a small shell helper for trace directory substitution and platform-specific quoting.
• Add Vitest coverage for the Windows cross-drive trace command case.

Why

On Windows, the previous command could generate a trace invocation like:

(cd 'p:\\project'; npx tsc --noEmit --generateTrace 'c:\\Users\\...\\traces')

That fails when the shell starts from a different drive. The process already receives the intended project path as cwd, so the explicit shell cd is unnecessary and makes the command less portable.

Validation

• corepack pnpm exec vitest run
• corepack pnpm run typecheck
• corepack pnpm exec eslint src/commands.ts src/shell.ts test/shell.test.ts