fix(NcAppSidebar): apply toggle offset transition only on sidebar transition

[ShGKme]

☑️ Resolves

• There is a transition for the sidebar toggle button
• It makes sense when the sidebar is opening/closing
• It looks like a glitch initially when it appears

🖼️ Screenshots

Slowed down to be more visible on gifs

🏚️ Before	🏡 After

🚧 Tasks

• Disable --app-sidebar-offset transition by default
• Enable --app-sidebar-offset transition when NcAppSidebar transition is active
• Make sure it has no changes for sliding

🏁 Checklist

• ⛑️ Tests are included or are not applicable
• 📘 Component documentation has been extended, updated or is not applicable
• 3️⃣ Backport to next requested with a Vue 3 upgrade

[Antreesy]

Makes sense

[ShGKme]

/backport to next

[backportbot]

The backport to next failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout next
git pull origin next

# Create the new backport branch
git checkout -b backport/5720/next

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick d5a2a7a9

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/5720/next

Error: No changes found in backport branch

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Learn more about backports at https://docs.nextcloud.com/server/stable/go.php?to=developer-backports.