Add Keybinds List to Help Menu

[EmeraldWither]

This PR adds a keybinds help page to Elastic, since it isn't nicely documented in one place anywhere. The keybinds are added dynamically based on what Hotkeys are registered using HotkeyManager (so adding extra hotkeys should appear here automatically), and are then converted to an intermediatory KeybindCaterory/Keybind class so it can be easily represented, tested, and then rendered to the screen. Everything should be unit tested.

[codecov]

Codecov Report

❌ Patch coverage is 90.06623% with 15 lines in your changes missing coverage. Please review.
✅ Project coverage is 78.37%. Comparing base (00c7168) to head (e668188).

Files with missing lines	Patch %	Lines
lib/widgets/keybinds_dialog.dart	91.66%	8 Missing ⚠️
lib/pages/dashboard_page.dart	86.79%	7 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #332      +/-   ##
==========================================
+ Coverage   78.20%   78.37%   +0.17%     
==========================================
  Files          93       94       +1     
  Lines        9413     9539     +126     
==========================================
+ Hits         7361     7476     +115     
- Misses       2052     2063      +11     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[Gold872]

This looks really good. I'll take a closer look at the KeybindsDialog implementation at a later point (it looks really complex) but I like this addition