feat: use Material You colors throughout Thunderbird

[farzanni]

Contribution Summary

Linked Issue/Ticket: Fixes #8340
RFC / Technical Design (if applicable): N/A

Description

Adds Android 12+ dynamic color support to Thunderbird while preserving the existing palette on older Android versions and on non-Android targets.

• Opts only ThunderbirdBoltTheme into platform dynamic colors; K-9 Mail keeps its current theme.
• Maps the Android Material 3 dynamic ColorScheme into Bolt's ThemeColorScheme while retaining Bolt's additional semantic colors.
• Overrides Thunderbird's legacy XML theme tokens in values-v31, so legacy surfaces and Compose screens use the same wallpaper-derived palette.
• Keeps the implementation at the Thunderbird app/theme boundary so shared K-9 behavior is unchanged.
• Adds a unit test covering the Material-to-Bolt color-role mapping.

Screen Shots

Not included because the palette is generated at runtime from the device wallpaper and no Android 12+ emulator/device is available in the current environment.

Testing

Before rebasing, the production implementation passed:

• :components:ui:bolt:compileAndroidMain
• :app-thunderbird:compileFossDebugKotlin
• :app-thunderbird:processFossDebugResources
• Full fossRelease build and release lint (0 lint errors)

After rebasing onto the latest main and adding the mapping test:

• git diff --check passed.
• ./gradlew :components:ui:bolt:jvmTest :components:ui:bolt:spotlessCheck :app-thunderbird:compileFossDebugKotlin :app-thunderbird:processFossDebugResources --no-daemon was attempted, but Gradle stopped during configuration because Google Maven returned HTTP 404 for the upstream-pinned com.android.application:9.2.1 plugin. No project task executed in that attempt.

Risks / Trade-offs

• Dynamic colors are available only on Android 12 (API 31) and newer; older Android versions keep the existing Thunderbird palette.
• Bolt-only info, success, and warning roles have no Material dynamic equivalents, so the existing Thunderbird values are retained.
• K-9 Mail is intentionally unchanged.

AI Disclosure

• This contribution does not include any changes created or assisted by AI.
• This contribution includes changes assisted by AI.
• This contribution includes changes created by AI.

Contribution Checklist

• I have read and affirm that my contribution adheres to Mozilla's Community Participation Guidelines
• This contribution is in Kotlin where possible
• This contribution does not use merge commits
• This contribution adheres to the existing codestyle (run gradlew spotlessCheck to check and gradlew spotlessApply to format your source code; will be checked by CI).
• This contribution does not break existing unit tests (run gradlew testDebugUnitTest; will be checked by CI).
• This contribution includes tests for new functionality and maintains tests for updated functionality.
• This contribution adheres to our Engineering process (RFC/Technical Design/ADR)
• This PR has a descriptive title and body that accurately outlines all changes made, and contains a reference to the issue it fixes.

[github-actions]

Missing report label. Set exactly one of: report: include, report: exclude OR report: highlight.

[farzanni]

Process update: I rebased this branch onto the latest main, corrected the commit attribution to my GitHub account, added a focused color-mapping test, and updated the PR body to match the current template with an accurate AI disclosure and verification notes. I also requested issue alignment/assignment on #8340. I do not have permission to apply repository labels; could a maintainer please add report: include?

[jbott-tbird]

Thank you @farzanni for your interest in helping us. At this time, we have decided to use the Thunderbird Bolt design system instead of Material You.