Fix dropdown menu backgrounds and settings popup theme matching

[WyattGorman]

Summary

Adds a theme-matched background color to the dropdown menus, and adds theme matched colored text and backgrounds to the settings popup window.

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update
• Refactoring (no functional changes)
• CI/CD or infrastructure change

Related Issues

N/A

Changes Made

-Adds a theme-matched background color to the dropdown menus

• Adds theme matched colored text and backgrounds to the settings popup window.

Testing

Tested in my local environment

• I have tested this locally
• I have added/updated tests that prove my fix/feature works
• All existing tests pass

Checklist

• My code follows the project's code style
• I have performed a self-review of my code
• I have commented my code where necessary (particularly complex areas)
• I have updated the documentation if needed
• My changes generate no new warnings
• No console.log, debug statements, or commented-out code

Screenshots (if applicable)

[Starosdev]

Thanks for the contribution @WyattGorman — the dialog theming fix is exactly the right approach. A few things to address before we can merge:

1. Target develop, not master

Please retarget this PR to the develop branch and rebase on latest develop to resolve the merge conflict.

2. Drop the panelClass changes in the HTML templates

The dropdown panel background is already handled globally in styles.scss via CSS custom properties:

```scss
.treo-theme-dark {
--mat-select-panel-background-color: #1e293b;
--mat-menu-container-color: #1e293b;
}
```

These cascade to the CDK overlay and Angular Material reads them directly — no panelClass on individual mat-select elements needed. Remove the panelClass="theme-select-panel" additions from both HTML templates and the .theme-select-panel SCSS block.

3. Remove the redundant mat-menu SCSS

Same reason — --mat-menu-container-color already covers .mat-mdc-menu-panel background. The .treo-theme-dark .mat-mdc-menu-panel and .mat-mdc-menu-item blocks in your styles.scss addition are duplicating existing behavior.

4. Fix a dead CSS selector

```scss
// This never matches — compound selector requires both classes on same element
.treo-theme-dark.mat-mdc-dialog-container .mdc-dialog__surface { ... }
```

treo-theme-dark is on body, mat-mdc-dialog-container is on the dialog — they're never on the same element. Remove this rule (the .treo-theme-dark .mat-mdc-dialog-surface selector below it is the correct form and does work).

What to keep: The panelClass: [theme, 'settings-dialog-panel'] additions in the three .ts files are correct and valuable. The .cdk-overlay-container .settings-dialog-panel.treo-theme-dark SCSS block is valid. Those are the real fix here.

[Starosdev]

Thanks for the contribution. This still needs changes before it can merge.

Blocking items:

1. Please retarget this PR from master to develop, then rebase on the latest develop. The PR is currently reported as conflicting, and the same conflicts reproduce locally in the settings templates plus dashboard/mobile settings TypeScript files.

2. Please remove the panelClass="theme-select-panel" additions from the settings templates and remove the related .theme-select-panel SCSS. Current develop already sets the Material overlay background colors globally with CSS variables, so the per-select panel class is redundant.

3. Please remove the redundant .mat-mdc-menu-panel / .mat-mdc-menu-item dark-mode SCSS additions. The menu container background is already handled globally.

4. Please remove the dead selector .treo-theme-dark.mat-mdc-dialog-container .mdc-dialog__surface; those classes are not on the same element, so that selector does not match. Keep the dialog panelClass approach for the settings dialogs and the valid overlay-container styling.

Once this is rebased onto develop and narrowed to the dialog theming fix, I can review again.