fix: Modernize build system to use vite and @nextcloud/vue version 8

[susnux]

1. Update @nextcloud/vue and @nextcloud/dialogs
2. Migrate to vite instead of webpack, otherwise the assets are ridiculously big (webpack fails tree shaking and results in 2.6MiB assets just for settings...).

[blizzz]

Please don't forget to set the milestone when opening a PR 😃

[github-actions]

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