TheGreatAzizi/Secure-Pastebin-Self-Hosted — reverse-engineered prompt

Build me a self hosted secure paste sharing app for sensitive text. I want people to write a note, optionally add a subject, and then have it encrypted in the browser before anything is uploaded, so the server only ever stores unreadable ciphertext. The decryption key should stay in the share link after the hash so it never gets sent to the server.

Make it easy to create links, including a normal full link and a shorter compact one. I want optional password protection, preset expiration times plus a custom date and time, and a burn after reading option. The writing box should support Markdown with a small toolbar, and the message should only be rendered as Markdown after it is decrypted. Add copy buttons for the share links and for the decrypted text.

Please make the interface clean, mobile friendly, and able to handle RTL languages well. It should be simple to host on a regular PHP and MySQL setup, with URL rewriting, plus a basic API and a human friendly API docs page. Look up current docs online if you need to.