fix: tmpo stats now lists projects in the same order every time

[DylanDevelops]

Updated the stats display to sort projects alphabetically in both period and all-time statistics for consistent and predictable output. This improves readability and makes it easier to locate specific projects in the stats.

Pull Request Checklist

• I have read and followed the contribution guidelines.
• My pull request targets the main branch of tmpo.
• I have tested these changes locally on my machine.

Description

This pull request improves the consistency and readability of project statistics output in the cmd/stats.go file by ensuring that project listings are displayed in alphabetical order. This affects both the period-based and all-time statistics views.

Display improvements:

• Project statistics in both ShowPeriodStats and ShowAllTimeStats are now sorted alphabetically for a consistent and predictable display order. [1] [2]
• Updated variable naming in ShowAllTimeStats for clarity and consistency (projects → allProjects).

Dependency update:

• Added the "sort" package import to support alphabetical sorting of project names.