Add badges/shields for ecosystem packages on provider pages

[AmitoVrito]

Description

Add PyPI badges and version info for each optional dependency on provider pages.

What to do

• On each provider page, show required package version badge, install command, link to docs
• Use shields.io badges for visual consistency

[AmitoVrito]

Thanks for your interest! I will assign it to you. Before you start, could you give the repo a ⭐ on the main repo (https://github.com/SynapseKit/SynapseKit)? It really helps with visibility for a new project. Looking forward to your PR!

[AmitoVrito]

Done — PyPI, Python version, license, and test count badges added to LLM providers overview in PR #44.