chore: create backup protobuf models [WPB-10575]

[vitorhugods]

WPB-10575 Cross Platform Backup: Write common backup / restore library

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PR Submission Checklist for internal contributors

• The PR Title

  • conforms to the style of semantic commits messages¹ supported in Wire's Github Workflow²
  • contains a reference JIRA issue number like SQPIT-764
  • answers the question: If merged, this PR will: ... ³

• The PR Description

  • is free of optional paragraphs and you have filled the relevant parts to the best of your ability

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What's new in this PR?

Issues

We need to (de)serialize data when storing backups.

Solutions

Use protobufs.
The idea here is to leverage the current protobuf generation and just build on top of it for backups.

When we upgrade to Kotlin 2.0+ we could replace PBandK and use KotlinX serialization for this. Unfortunately we're not there yet :'(

Notes

This is an initial / draft version that will be expanded in future PRs.

Testing

N/A

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PR Post Merge Checklist for internal contributors

• If any soft of configuration variable was introduced by this PR, it has been added to the relevant documents and the CI jobs have been updated.

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References

1. https://sparkbox.com/foundry/semantic_commit_messages
2. https://github.com/wireapp/.github#usage
3. E.g. feat(conversation-list): Sort conversations by most emojis in the title #SQPIT-764.

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

Test Results

3 305 tests  ±0   3 198 ✅ ±0   4m 27s ⏱️ -43s
  564 suites ±0     107 💤 ±0 
  564 files   ±0       0 ❌ ±0 

Results for commit cc93964. ± Comparison against base commit 08c0cff.

♻️ This comment has been updated with latest results.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 54.03%. Comparing base (08c0cff) to head (cc93964).

Additional details and impacted files

@@                      Coverage Diff                      @@
##           epic/multiplatform-backup    #3116      +/-   ##
=============================================================
- Coverage                      54.03%   54.03%   -0.01%     
=============================================================
  Files                           1246     1246              
  Lines                          36152    36152              
  Branches                        3656     3656              
=============================================================
- Hits                           19534    19533       -1     
  Misses                         15208    15208              
- Partials                        1410     1411       +1     

see 3 files with indirect coverage changes

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[datadog-wireapp]

Datadog Report

Branch report: chore/add-protobuf-models-for-backup
Commit report: 87f4bc0
Test service: kalium-jvm

✅ 0 Failed, 3198 Passed, 107 Skipped, 29.69s Total Time