Expose ResourceExtender API

[AndrewTwydell]

What It Does
Dependent on #437
Adds resourceExtender class to exposed API, allowing extenders to get our API and add actions to resource types.

Review Checklist
I certify that I have:

• tested my changes
• added/updated automated tests
• updated the changelog
• considered whether the docs need updating
• followed the contribution guidelines

Additional Comments

[codecov-commenter]

Codecov Report

❌ Patch coverage is 67.21311% with 20 lines in your changes missing coverage. Please review.
✅ Project coverage is 65.30%. Comparing base (39d7ed1) to head (31a799f).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...ackages/vsce/src/extending/CICSResourceExtender.ts	33.33%	10 Missing ⚠️
...ges/vsce/src/resources/actions/LocalFileActions.ts	50.00%	4 Missing ⚠️
...kages/vsce/src/resources/actions/ProgramActions.ts	66.66%	2 Missing ⚠️
...s/vsce/src/resources/actions/TransactionActions.ts	66.66%	2 Missing ⚠️
packages/vsce/src/trees/ResourceInspectorUtils.ts	0.00%	1 Missing ⚠️
...es/vsce/src/trees/ResourceInspectorViewProvider.ts	80.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #438      +/-   ##
==========================================
+ Coverage   65.16%   65.30%   +0.13%     
==========================================
  Files         179      180       +1     
  Lines        4263     4294      +31     
  Branches      596      598       +2     
==========================================
+ Hits         2778     2804      +26     
- Misses       1485     1490       +5     

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