Handling copy failures and retry capability

[vkWeb]

Summary

This PR brings in the capability to retry failed copies and detection of failing copies.

Manual verification steps performed

To generate copy error state on the frontend, I raised an exception from the backend copy function. These are the checks I've performed:-

1. Checked whether error in the changesForSyncing table are detected. (happens when copy fails due to a known reason)
2. Checked whether task errors are detected. (happens due to abnormal task termination or unhandled exceptions)
3. Checked whether importing from channels errors out.
4. Checked whether copying completes.
5. Checked whether retrying completes successfully when the exception is removed from the backend code.
6. Checked whether after multiple failures, retrying still reaches success upon exception removal.
7. Copying multiple nodes together by selecting them works as expected.
8. When copy is failed, the node can be removed.

Screenshots (if applicable)

The below screenshot is a work in progress. I need to make some CSS changes to make the UI look as it is expected.

The below is the UI design that is expected.

Does this introduce any tech-debt items?

I tested the code thoroughly and I've the following concerns, they might be or might not be tech debts depending on how we treat them, but listing them out for clarity:-

1. Due to the architectural design of this PR, signing out and signing in doesn't persist the error state.
2. The error state doesn't get synced between multiple users.

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Reviewer guidance

References

Closes #2850.
Closes #3914.

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Contributor's Checklist

PR process:

• If this is an important user-facing change, PR or related issue the CHANGELOG label been added to this PR. Note: items with this label will be added to the CHANGELOG at a later time
• If this includes an internal dependency change, a link to the diff is provided
• The docs label has been added if this introduces a change that needs to be updated in the user docs?
• If any Python requirements have changed, the updated requirements.txt files also included in this PR
• Opportunities for using Google Analytics here are noted
• Migrations are safe for a large db

Studio-specifc:

• All user-facing strings are translated properly
• The notranslate class been added to elements that shouldn't be translated by Google Chrome's automatic translation feature (e.g. icons, user-generated text)
• All UI components are LTR and RTL compliant
• Views are organized into pages, components, and layouts directories as described in the docs
• Users' storage used is recalculated properly on any changes to main tree files
• If there new ways this uses user data that needs to be factored into our Privacy Policy, it has been noted.

Testing:

• Code is clean and well-commented
• Contributor has fully tested the PR manually
• If there are any front-end changes, before/after screenshots are included
• Critical user journeys are covered by Gherkin stories
• Any new interactions have been added to the QA Sheet
• Critical and brittle code paths are covered by unit tests

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Reviewer's Checklist

This section is for reviewers to fill out.

• Automated test coverage is satisfactory
• PR is fully functional
• PR has been tested for accessibility regressions
• External dependency files were updated if necessary (yarn and pip)
• Documentation is updated
• Contributor is in AUTHORS.md

[bjester]

Overall, the Dexie queries look like they should use other querying methods than just toArray
https://dexie.org/docs/Collection/Collection.first()

[bjester]

Nothing is using the resulting promise from Promise.allSettled

[vkWeb]

Using Promise.allSettled so that the rejections from the underlying promise doesn't result in console errors. Because here we don't need to handle rejected promises from copyContentNode. Does it make sense sir?

[vkWeb]

Should I use an empty catch here? (maybe a better alternative)

[vkWeb]

@bjester closing this. Will re-open a fresh PR that will target hotfixes. Will keep in mind the issues raised here.