fix(notifications): use last event instead of oldest when recoverying from 404 [WPB-267]

[github-actions]

Cherry pick from the original PR:

• fix(notifications): use last event instead of oldest when recoverying from 404 [WPB-267] #2037

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⚠️ Conflicts during cherry-pick:

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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

• When attempting to fetch the oldest possible event from the api, some issue prevents us from moving on. See WPB-4442.

• We leave open a time gap between registering client and performing slow-sync until we first fetch the last notification from the backend. Which can lead to some events being lost.

Solutions

1. Move the responsibility of fetching the last notification from remote outside of the repository, and into slow sync. That now fetches and saves the most recent event IDs after successful workflow if there's no previously processed event ID.
   This follows more closely the general sync documentation.

2. During incremental sync recovery, clears the last processed event ID and restarts slow sync for Client or EventNotFound failures. Which, as described in 1, will cause the fetching of the last remote event.

3. Refactored method names to align with these changes for better clarity.

Testing

Tested manually by changing the lastProcessedEventId in the database to some garbage, which led to a 404 and successful recovery.

Test Coverage

• I have added automated test to this contribution

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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.

[github-actions]

Unit Test Results

   432 files  ±0     432 suites  ±0   3m 21s ⏱️ + 1m 23s
2 353 tests +2  2 250 ✔️ +2  103 💤 ±0  0 ❌ ±0 

Results for commit acf3474. ± Comparison against base commit 01e8e23.

♻️ This comment has been updated with latest results.

[datadog-wireapp]

Datadog Report

All test runs b48a3c6 🔗

✅ 2 Total Test Services: 0 Failed, 0 with New Flaky, 2 Passed

Test Services

Service Name	Failed	Known Flaky	New Flaky	Passed	Skipped	Wall Time	Branch View
kalium-ios	0	0	0	1615	31	10.01s	Link
kalium-jvm	0	0	0	2250	103	13m 38s	Link