Update stirling-pdf to version v0.34.0

[nmfretz]

🤖 This is an automated pull request to update stirling-pdf to version v0.34.0. This PR must be reviewed and tested before merging.

[nmfretz]

🤖 This is an automated summary of installation tests for stirling-pdf:

• ✅ App successfully installed in umbrel-dev instance
• ✅ App successfully listed in umbrel.yaml
• ✅ App UI successfully returns a 200 status code
• 📸 Screenshot of the app:
  

This PR must still be reviewed and tested before merging.

[nmfretz]

@sharknoon I'd love your thoughts on this Stirling PDF update 🙏

There's a breaking change for versions older than 0.28.0 that requires an intermediate update before updating to 0.34.0:
https://github.com/Stirling-Tools/Stirling-PDF/releases

With this update also comes some breaking changes to our database file for additional security
Any users updating from a version older than 0.28.0 will need to first update to a version after that and restart the application. After this the application can be updated to 0.34.0+ as normal
This will allow the database to then migrate to the 0.34.0 version

The first version of Stirling on the umbrel app store was 0.25.0, and then we updated to >0.28 at the end of August of this year, so it's unlikely but still possible that users could be on an old version of the app that requires an intermediate update.

It would be really nice not to have to create a pre-start script that migrates users similar to what we've done for Nextcloud and Gitlab because they are cumbersome and they effectively need to stick around forever.

Stirling PDF doesn't store any data that's critical for users, correct? Like it just stores settings and logs? If so, I'm thinking we could just add something like this to the release notes:

🚨 If you are currently running a version of Stirling PDF that is older than 0.28.0, you will need to uninstall the app and then reinstall Stirling PDF. No data will be lost and....

[sharknoon]

I have created a pre-start hook in this PR here: #1864
@nmfretz You can find more information in this PR :)

[github-actions]

🎉   Linting finished with no errors or warnings   🎉

Thank you for your submission! This is an automated linter that checks for common issues in pull requests to the Umbrel App Store.

Please review the linting results below and make any necessary changes to your submission.

Linting Results

Severity	File	Description
ℹ️	stirling-pdf/docker-compose.yml	Potentially using unsafe user in service "app": The default container user "root" can lead to security vulnerabilities. If you are using the root user, please try to specify a different user (e.g. "1000:1000") in the compose file or try to set the UID/PUID and GID/PGID environment variables to 1000.

Legend

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❌	Error: This must be resolved before this PR can be merged.
⚠️	Warning: This is highly encouraged to be resolved, but is not strictly mandatory.
ℹ️	Info: This is just for your information.

[nmfretz]

It would be really nice not to have to create a pre-start script that migrates users similar to what we've done for Nextcloud and Gitlab because they are cumbersome and they effectively need to stick around forever.

• Add pre-start migration script for Stirling PDF updates #1864 confirmed that stirling persists preferences, but no important user data.
• Additional testing shows that users can upgrade from 0.25 to 0.34.0 without issue. If for some reason the update is unsuccessful, there is no data that is lost, so a user can just re-install stirling. This keeps things clean without the need for a lifecycle hook.
• Retested fresh install and app update.