Add AGENTS.md with Cursor Cloud development environment instructions

[barredterra]

Adds AGENTS.md with Cursor Cloud-specific instructions for future agents, covering:

• REPO_NAME=ask_alyf override needed because the workspace directory is /workspace
• PATH configuration to use Node.js 24 from /usr/local instead of nvm-managed Node.js 22
• Python 3.14 requirement and installation method
• Service startup procedure (MariaDB, Redis, bench start)
• Test commands and the known soft-link mode test caveat
• Linting and asset build commands
• Login credentials for the dev site

Environment Demo

demo_ask_alyf_app_running.mp4
Ask ALYF Settings and Conversation pages loaded successfully on http://ask-alyf.localhost:8000.

Hello World conversation form
Ask ALYF Settings page

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