chore: add dev.sh for Linux/WSL dev loop

dev.ps1 uses a watchfiles workaround for a Windows-only event loop
limitation (Selector loop can't do asyncio.create_subprocess_exec).
On Linux/WSL that limitation doesn't exist, so dev.sh uses uvicorn
--reload directly — one terminal, Ctrl+C cleans up both processes.

Also updates CLAUDE.md to reference both scripts side by side,
and normalises CRLF → LF on that file.

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

Author: AlpineArchitecture