New App: Tibber Price Forecast

[cruschke]

This PR adds a new community app that displays real-time electricity price forecasts for Tibber customers.

What the Tibber app does:

The Tibber Price app shows a 30-hour electricity price forecast on your Tidbyt with 30-minute granularity (60 half-hourly bars). It uses gradient color coding from green (cheapest) to red (most expensive) to help users identify the best times to use electricity and save money. The app also displays historical consumption data with intelligent efficiency coloring that considers both usage amount and price timing. Features include smart caching for reliability, automatic fallback if the API is unavailable, and a visual design that matches the official Tibber mobile app experience.

[tidbyt]

⚠️ The automated review process is experimental and likely has bugs. Please bear with us as we iron out the kinks and enable you to ship changes at high velocity 🚀

Next Steps

Hello! Thank you so much for your change 🤜 🤛 . There are a few things you need to do:

• Sign the CLA if you haven't already
• Ensure your build is green! Any problem will display a proposed solution to try out
• Get a review, either by Tidbyt Bot or by a Tidbyt engineer

Manual Review Required

Hang tight! A Tidbyt engineer will be by shortly to review your change. Here is what they will be looking for:

	Test	Details
✅	App Dir	All files are in a single app directory
🟡	Modules	Usage of cache.star requires review
✅	Original Author	The original author matches the PR author