Remove "local upload" / `report_code` feature

[Swatinem]

The "local upload" feature currently works by passing a report_code to all the various upload-related CLI commands and API calls.

The upload processing is then run as usual, but results are stored slightly differently:

• The report_json is stored once per commit.
• But a different chunks file is stored depending on the report_code.

We can thus end up in a situation where the report_json/chunks get out of sync, and a "local upload" corrupts an existing commit report by overwriting its report_json with one that does not correspond to the main chunks file anymore.

For this reason, I believe that the "local upload" feature is fundamentally broken. We should thus work towards deprecating and removing it.

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Removing the "local upload" and report_code feature also opens up the possibility to tackle some further internal refactorings:

• Streamline Commit/Report tables/concepts/code #2617
• Move coverage reports to a single file #3015

---

• Deprecate "local upload" related commands codecov-cli#679
• Deprecate the "local upload" ReportResults endpoints codecov-api#1291
• Remove "local upload" related save_report_results task worker#1214
• Clean up some report_code usage umbrella#63
• Fully remove and disallow non-default report_code umbrella#81
• Cleanup staticanalysis and local-upload related entities umbrella#80

[Swatinem]

done