Add: WebRTC P2P Signal & Data Channel Testing Studio

[Akshatshukla-25]

What does this PR do?

Closes #814

Adds WebRTC P2P Signal & Data Channel Testing Studio (tools/webrtc-testing-studio.html) under the Browser & Network category. The tool provides a client-side WebRTC playground for testing peer connections, inspecting SDP offers/answers, gathering ICE candidates with custom STUN servers, and exchanging real-time P2P DataChannel messages with latency measurement.

Type of Change

• New tool
• Enhancement to existing tool
• Bug fix
• Documentation update
• Build system / infrastructure

Screenshot

Checklist

• I have read the Contributing Guide
• My branch follows the naming convention (add/tool-name, feat/description, or fix/description)
• I have tested my changes locally in at least one modern browser

For new tools:

• The tool is a single self-contained .html file in the tools/ folder
• The filename is kebab-case (webrtc-testing-studio.html)
• I added an entry to data/tools.json with all required fields
• I added a screenshot as tools/webrtc-testing-studio.png next to the HTML file
• No JS frameworks or heavy UI libraries
• I ran node scripts/sort-norm.js data/tools.json to sort and normalize the tools registry
• I ran node scripts/build.js and verified the landing page renders correctly