refactor(v3): Remove all references to temporary downloads folder

[traeok]

Proposed changes

Removes the following settings and any code related to the temp folder (creation, cleanup, etc.):

Release Notes

Milestone: vNext

Changelog:

• Breaking: Zowe Explorer no longer uses a temporary directory for storing Data Sets and USS files. All settings related to the temporary downloads folder have been removed. In order to access resources stored by Zowe Explorer v3, refer to the FileSystemProvider documentation for information on how to build and access resource URIs. Extenders can detect changes to resources using the onResourceChanged function in the ZoweExplorerApiRegister class.

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] Enhancement (non-breaking change which adds or improves functionality)
• [x] Breaking change (a change that would cause existing functionality to not work as expected)
• [x] Documentation (Markdown, README updates)
• [ ] Other (please specify above in "Proposed changes" section)

Checklist

General

• [x] I have read the CONTRIBUTOR GUIDANCE wiki
• [ ] A GIF or screenshot is included in the PR for visual changes
• [x] The pre-publish command has been executed:
  • v2 and below: yarn workspace vscode-extension-for-zowe vscode:prepublish
  • v3: pnpm --filter vscode-extension-for-zowe vscode:prepublish

Code coverage

• [x] There is coverage for the code that I have added
• [x] I have added new test cases and they are passing
• [x] I have manually tested the changes

Deployment

• [x] I have added developer documentation (if applicable)
• [ ] Documentation should be added to Zowe Docs
  • If you're an outside contributor, please post in the #zowe-doc Slack channel to coordinate documentation.
  • Otherwise, please check with the rest of the squad about any needed documentation before merging.
• [ ] These changes may need ported to the appropriate branches (list here):

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 92.73%. Comparing base (52e5de7) to head (ad328d2).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## next #2980 +/- ## ========================================== + Coverage 92.68% 92.73% +0.05% ========================================== Files 111 109 -2 Lines 11017 10904 -113 Branches 2293 2320 +27 ========================================== - Hits 10211 10112 -99 + Misses 804 790 -14 Partials 2 2 ```

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[traeok]

SonarCloud has spotted existing code duplication from previous contributions. Existing code duplication can be addressed in a separate PR.

[sonarcloud[bot]]

Quality Gate failed

Failed conditions
30.3% Duplication on New Code (required ≤ 3%)

See analysis details on SonarCloud