rtmp-services: Add zap.stream

[v0l]

Description

Adds zap.stream to the services.json

Motivation and Context

zap.stream is an open source custom streaming server built on ffmpeg in rust. I run and develop the software with funding from OpenSats

UI: https://github.com/v0l/zap.stream Server: https://github.com/v0l/zap-stream-core

How Has This Been Tested?

Tested locally in OBS 33.0.2

Types of changes

• Tweak (non-breaking change to improve existing functionality)

Checklist:

• [x] My code has been run through clang-format.
• [x] I have read the contributing document.
• [x] My code is not on the master branch.
• [x] The code has been tested.
• [x] All commit messages are properly formatted and commits squashed where appropriate.
• [x] I have included updates to all appropriate documentation.