Add Phases

[mxtmx]

Adds a flexible phase management system for FTC match time periods. Includes:

• Phase class for defining named time periods with configurable durations and time units
• PhaseManager for automatic phase transitions based on elapsed match time with listener callbacks
• Comprehensive unit tests covering initialization, transitions, and edge cases

Allows teams to easily structure autonomous and teleop logic around match phases with automatic time-based transitions.

[opi3636]

Thank you very much for your PR.
I have some questions about the PhaseManager class.

• Why is everything static? To me, it seems better for it to be an object rather than static methods.
• Why is the index of the current and previous Phase stored instead of the objects themself? It introduces some unnecessary logic that can be a bit confusing.