Add Shift Clock app

[Psauter417]

Description

Adds Shift Clock, a configurable work-shift clock showing the current time, pre-shift countdown, remaining shift time, and visual progress.

Features include:

• Configurable start and end times
• Normal and overnight shift support
• One-hour pre-shift countdown beginning at SHIFT IN 60M
• Red progress bar during a shift and green completion state
• 12-hour and 24-hour display options
• Location-based timezone configuration

Validation

• pixlet check apps/shiftclock
• Rendered and visually inspected at 64x32 pixels in off-duty, pre-shift, active-shift, and completed states

[tidbyt]

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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

Automated Review Successful

Magical robots have reviewed your change and it looks good to go! 🤖

	Test	Details
✅	App Dir	All files are in a single app directory
✅	Modules	Only safe modules, without side-effects, are loaded
✅	Original Author	The original author matches the PR author