🐛 - Cap home shortcuts to 4 to prevent Android crash

[guytepper]

Summary

• Slice favorite routes to a max of 4 before calling Shortcuts.setShortcuts
• Prevents IllegalArgumentException: Max number of dynamic shortcuts exceeded on Android devices whose getMaxShortcutCountPerActivity() is lower than the number of saved favorites (reported on Samsung SM-A155F running Android 16). iOS also caps quick actions at 4, so the same constant is safe cross-platform.

Test plan

• Add 5+ favorite routes on Android and verify the app no longer crashes
• Confirm the first 4 favorites still appear as home-screen shortcuts on Android and iOS

[gemini-code-assist]

Code Review

This pull request limits the number of home screen shortcuts to four to prevent potential crashes on Android devices. Feedback includes a critical fix for a potential ClassCastException on Android caused by passing a boolean value to the subtitle field instead of a string or undefined, and a suggestion to move the MAX_HOME_SHORTCUTS constant to the top level of the file for better maintainability.

[gemini-code-assist]

The expression !route.label && toText(route) evaluates to false when route.label is present. Passing a boolean value to Shortcuts.setShortcuts for a field that expects a string (like subtitle) can cause a ClassCastException on the native Android side when the library attempts to call getString("subtitle"). It is safer to use a ternary operator to ensure the value is either a string or undefined.

Suggested change

	subtitle: !route.label && toText(route),
	subtitle: !route.label ? toText(route) : undefined,

[gemini-code-assist]

While defining the constant here works, it's generally better practice to define configuration constants like MAX_HOME_SHORTCUTS at the top level of the file. This improves visibility and maintainability, especially if the value needs to be referenced elsewhere in the future.