Update README.md

v3.0.0 release

Proxima v3.0.0

REST API
  You can now use Proxima from any app, script, or tool.
  Just POST to localhost:3210/v1/chat/completions  same format as OpenAI.
  Works with anything that supports custom OpenAI endpoints.

Python & JS SDKs
  No install needed  just drop proxima.py or proxima.js in your project.
  One function for everything: client.chat('hello', model='claude')

New Tools
  - math_search / image_search  search with formulas or find images
  - analyze_file  send local files to any AI for review
  - show_window / hide_window  control the app from your IDE
  - new_conversation / get_provider_status  manage sessions via MCP

Multi-AI Compare
  Send one prompt to all 4 AIs at once, get side-by-side answers.

Update README with correct GitHub links