Add NicePrice plugin

[MathisBls]

NicePrice shows game prices from 50+ stores right in Steam (Library + Store pages). Uses GG.deals API to find the best retail/keyshop deals and historical lows.

• Price bar overlay in Library
• Sidebar widget on Store pages
• API key settings panel
• Lua backend, no external deps

Repo: https://github.com/MathisBls/NicePrice

[Copilot]

Pull request overview

Adds the NicePrice plugin to the plugin database by registering it as a git submodule.

Changes:

• Add a new git submodule entry pointing to https://github.com/MathisBls/NicePrice.git.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[BarterClub]

Went ahead and downloaded the repo and tested on stable. The plugin settings does not work at the moment. So cant test the rest of the app.

[MathisBls]

Went ahead and downloaded the repo and tested on stable. The plugin settings does not work at the moment. So cant test the rest of the app.

Hi, have you built and relaunched Steam? I just pushed a new version that includes the build output, it should work now