v1.0.1: Refactor tree progression and update UI elements

This commit introduces the following changes:

- Refactored the tree progression logic in `ProgressFragment` and `StatsChartFragment` to use percentage-based progress and updated tree images.
- Added new tree images (cover, part_1 to part_8).
- Updated the daily goal to 10,000 steps in settings and related UI elements.
- Adjusted the step increment in `ForestFragment` to 500.
- Added an ImageView for the tree in `fragment_stats_chart.xml`.
- Updated Chinese translations for "tree" to "书".
- Updated the demo media in `README.md`.
- Added `goal` to `StatsDetailsState` and updated `StatsDetailsViewModel` accordingly.