Add samples that show how to extend ZE

[t1m0thyj]

Proposed changes

This PR is inspired by the VS Code samples repo and the WebView sample added in #2418. It adds 3 more samples:

• Menu Item Sample
• Tree View Sample
• USS Profile Sample

How to test

• Open each of the sample project folders (e.g., samples/menu-item-sample) in VS Code.
• Press F5 to launch the sample extension.

Release Notes

N/A

Types of changes

What types of changes does your code introduce to Zowe Explorer?
Put an x in the boxes that apply

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Updates to Documentation or Tests (if none of the other choices apply)

Checklist

Put an x in the boxes that apply. You can also fill these out after creating the PR. If you're unsure about any of them, don't hesitate to ask. We're here to help! This checklist will be used as reference for both the contributor and the reviewer

• I have read the CONTRIBUTOR GUIDANCE wiki
• PR title follows Conventional Commits Guidelines
• PR Description is included
• gif or screenshot is included if visual changes are made
• yarn workspace vscode-extension-for-zowe vscode:prepublish has been executed
• All checks have passed (DCO, Jenkins and Code Coverage)
• I have added unit test and it is passing
• I have added integration test and it is passing
• There is coverage for the code that I have added
• I have tested it manually and there are no regressions found
• I have added necessary documentation (if appropriate)
• Any PR dependencies have been merged and published (if appropriate)

Further comments

[codecov]

Codecov Report

Patch coverage has no change and project coverage change: +0.02% 🎉

Comparison is base (ab67b38) 92.61% compared to head (86f806f) 92.63%.
Report is 3 commits behind head on main.

❗ Current head 86f806f differs from pull request most recent head 96402bf. Consider uploading reports for the commit 96402bf to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2425      +/-   ##
==========================================
+ Coverage   92.61%   92.63%   +0.02%     
==========================================
  Files          98       98              
  Lines        9425     9425              
  Branches     1952     1952              
==========================================
+ Hits         8729     8731       +2     
+ Misses        695      693       -2     
  Partials        1        1              

see 1 file with indirect coverage changes

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

[t1m0thyj]

New samples are ready for review. The Zowe Explorer Samples CI workflow is failing until we have a version of zowe-explorer-api package published with webview support 😋

[traeok]

Currently running into an ESLint error when trying to build/watch uss-profile-sample:

Other than that, tested all the samples and LGTM 🙂

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
4 Code Smells

No Coverage information
0.0% Duplication

[traeok]

LGTM, thanks @t1m0thyj - hoping these samples will incentivize/inspire Zowe Explorer extenders 🥳