feat: Create tree component

[MarkoOleksiyenko]

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• Read the Contributing Guidelines
• Reference your PR to an issue that was discussed ahead of time
• The PR should contain a clear description of the problem it solves
• Ideally, include a test that fails without this PR but passes with it.

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• Run the unit tests with npm run test
• Run the linting with npm run lint
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[codecov]

Codecov Report

Attention: Patch coverage is 87.40741% with 17 lines in your changes missing coverage. Please review.

Project coverage is 91.87%. Comparing base (de19c38) to head (bb403cf).
Report is 7 commits behind head on main.

Files with missing lines	Patch %	Lines
core/src/components/tree/tree.ts	88.29%	4 Missing and 7 partials ⚠️
...ar/bootstrap/src/components/tree/tree.component.ts	72.22%	5 Missing ⚠️
core-bootstrap/src/components/tree/tree.ts	66.66%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #999      +/-   ##
==========================================
- Coverage   92.11%   91.87%   -0.24%     
==========================================
  Files          94       98       +4     
  Lines        2535     2670     +135     
  Branches      421      438      +17     
==========================================
+ Hits         2335     2453     +118     
- Misses        130      140      +10     
- Partials       70       77       +7     

Flag	Coverage Δ
e2e	83.25% <87.40%> (+0.22%)	⬆️
unit	84.48% <57.44%> (-1.31%)	⬇️

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[ExFlo]

Hi the screenreader is not fully working when expanding / collapsing the node.

[ExFlo]

Fix the keyboard navigation with screenreader

[quentinderoubaix]

Some comments, thanks @MarkoOleksiyenko for this new component !

[quentinderoubaix]

Tagged all fixed comments as resolved, thx @MarkoOleksiyenko !