feat(thundermail-mvp): integrate sign in with thundermail and scan qr code buttons

[rafaeltonholo]

Changes

• Add thundermail_onboarding_enabled feature flag
• Add ThundermailButtonPanel with sign-in with Thundermail and Scan QR code
• Add ThundermailButtonPanel to migration screen
• Integrate Thundermail sign-in flow via QR code import
• Add :feature:thundermail:internal:common module
• Implement navigation setup for Thundermail QR code flow
• Wire Thundermail sign-in navigation to migration screen
• Wire OAuth flow on "Sign with Thundermail" button
• Reduce vertical spacing in ThundermailButtonPanel for better visual balance on smaller screens

Screenshots

Small phone - Portrait - Migration Screen
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Small phone - Portrait - Add Account
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Small phone - Landscape - Migration Screen
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Small phone - Landscape - Add Account
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Large phone - Portrait - Migration Screen
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Large phone - Portrait - Add Account Screen
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Large phone - Landscape - Migration Screen
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Large phone - Landscape - Add Account Screen
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Tablet - Portrait - Migration Screen
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Tablet - Portrait - Add Account
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Tablet - Landscape - Migration Screen
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Tablet - Landscape - Add Account
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K9-Mail
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[wmontwe]

I think listing the commits as part of the PR body, doesn't add value. If you consider this information is important, it should be added to the commit message as: cherry picked from commit e0052a88199c01a090efe3609cd75b30c82b8b8b. Then it's visible when you review commit by commit.

[rafaeltonholo]

I think listing the commits as part of the PR body, doesn't add value. If you consider this information is important, it should be added to the commit message as: cherry picked from commit e0052a88199c01a090efe3609cd75b30c82b8b8b. Then it's visible when you review commit by commit.

The idea was to help the reviewer to know what the range of commits should be reviewed in this PR, as this contains all the commits from the parent PR as well.

Maybe a diff statement would be better? I'm still trying to find the best solution for situations like that

[dani-zilla]

It does seem like importing via QR code still has an issue where you have to go into account settings to refresh the account monogram logo to be the initials on the account rather than "XX"

Besides that, I'm not seeing the crash I saw when importing accounts without the QR code.

However, I have noticed that if you use the QR code to pull up your account, don't sign in, choose later, go to the account and select server settings, it'll direct you to sign in. You can sign in, but nothing updates or shows that it's a functional account until you tap "Sync account."

[dani-zilla]

Would we ever need to execute everything if we don't have the email address, at least? Also, do we want to check for empty strings here? It should be pretty controlled, I take it, but I noticed we test for null specifically on them in the test, and wondered if empty strings would be similarly invalid

[rafaeltonholo]

Would we ever need to execute everything if we don't have the email address, at least?

The actual email derives from either the preferred_username or email field within the id_token. At least one of these two must be available, with preferred_username being the first pick.

Also, do we want to check for empty strings here? It should be pretty controlled, I take it, but I noticed we test for null specifically on them in the test, and wondered if empty strings would be similarly invalid

Although I think it is unlikely that an id_token would return an empty string for these fields, I don't think it hurts to check them. I would consider an empty string as a malformed claim in an id_token, but I need to double-check if that is really a case.

[rafaeltonholo]

It does seem like importing via QR code still has an issue where you have to go into account settings to refresh the account monogram logo to be the initials on the account rather than "XX"

Besides that, I'm not seeing the crash I saw when importing accounts without the QR code.

However, I have noticed that if you use the QR code to pull up your account, don't sign in, choose later, go to the account and select server settings, it'll direct you to sign in. You can sign in, but nothing updates or shows that it's a functional account until you tap "Sync account."

It does seem like importing via QR code still has an issue where you have to go into account settings to refresh the account monogram logo to be the initials on the account rather than "XX"

This is being handled by #10959

Besides that, I'm not seeing the crash I saw when importing accounts without the QR code.

However, I have noticed that if you use the QR code to pull up your account, don't sign in, choose later, go to the account and select server settings, it'll direct you to sign in. You can sign in, but nothing updates or shows that it's a functional account until you tap "Sync account."

This is the same behaviour the current version on main has when importing from a QR code.