fix(ui_auth): make light text on _EmailVerificationBadge legible

[qwezey]

Description

• Reduced the opacity of the badge's background to make light text in a dark theme more legible
• Dark text in a light theme is still legible
• The reduced opacity also makes the color more appealing

Related Issues

This PR resolves issue #18

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[EArminjon]

I think it could be better to expose this color through a dedicated parameter. In fact, it could be good to have the possibility to override every UI widget of this package to custom them as close as client app current design.
It could be really fantastic to be able to have the hand on every things :/ !

[qwezey]

@EArminjon For this PR, do you think I should allow the client to override the whole decoration property of the Container or only the color property of the BoxDecoration?

[EArminjon]

I'm not a maintainer, it's just a global question around this package and maybe the real fix behind this needs.

[lesnitsky]

it could be good to have the possibility to override every UI widget of this package to custom them as close as client app current design.

Styling API is in place and contributions on making anything configurable are welcome.

In general, here's how styling should be taken care of:

• extend FirebaseUIStyle
• override applyToMaterialTheme or applyToCupertinoTheme if necessary (see this example)
• define a property on a relevant widget (like here)
• define Set<FirebaseUIStyle> styles on a screen level (like here)
• use FirebaseUIStyle.ofType<T extends FirebaseUIStyle> (like here) to get a relevant style object from build context

In this specific issue, we could create an EmailVerificationBadgeStyle object and have a configurable backgroundColor defined there.

@qwezey would you be willing to update your PR accordingly?

[lesnitsky]

please make this configurable as mention here.

[russellwheatley]

Hey @qwezey - will you be following up on this PR?

[cmjordan42]

@lesnitsky @russellwheatley Can we proceed with merging this PR? It is a bug fix but requests to incorporate non-critical enhancements seem to be stalling it. We are at a 0 currently and this change seems like it would get us to a 1, so it seems prudent to keep any enhancements to get to a 2 separate from this.