bug(tabs): customizable tokens background-color and foreground-color have no effect

### Is this a regression?

- [ ] Yes, this behavior used to work in the previous version

### The previous version in which this bug was not present was

_No response_

### Description

When trying to override tabs background and foreground colors
```typescript
@include mat.tabs-overrides(
(
background-color: red,
foreground-color: white,
)
);
```
nothing happens.

Overridden colors take effect only when apply `backgroundColor` directive on tabs component.

Moreover after applying `backgroundColor` directive customizable tokens `active-label-text-color` and `active-indicator-color` aren't being applied anymore.
```typescript
@include mat.tabs-overrides(
(
background-color: red,
foreground-color: white,
active-label-text-color: green,
active-indicator-color: green,
)
);
```
In this case using directive `color` on tabs component solve the problem.

### Reproduction

StackBlitz link: https://stackblitz.com/edit/2xvcvpsg
Steps to reproduce:
It's self-explanatory

### Expected Behavior

Customizable tokens should apply regardless directives `backgroundColor` and `color`

### Actual Behavior

Customizable tokens are applied only when directives `backgroundColor` and `color` are used on tab component.

### Environment

Angular CLI: 19.0.4
Node: 22.11.0
Package Manager: pnpm 9.13.2
OS: linux x64

Angular: 19.0.3
... animations, common, compiler, compiler-cli, core, forms
... language-service, platform-browser, platform-browser-dynamic
... platform-server, router

Package Version
-----------------------------------------------------------
@angular-devkit/architect 0.1900.4 (cli-only)
@angular-devkit/build-angular 19.0.4
@angular-devkit/core 19.0.4
@angular-devkit/schematics 19.0.4
@angular/cdk 19.0.2
@angular/cli 19.0.4
@angular/material 19.0.2
@angular/material-luxon-adapter 19.0.2
@angular/ssr 19.0.4
@schematics/angular 19.0.4
rxjs 7.8.1
typescript 5.6.3
webpack 5.97.1
zone.js 0.15.0

リンクされた StackBlitz の再現から始め、tabs-overrides トークンと backgroundColor および color ディレクティブを比較します。これらのディレクティブが tabs のスタイルにどのような影響を与えるかを追跡し、その後、background-color、foreground-color、active-label-text-color、active-indicator-color がどちらのディレクティブも指定しなくてもすべて適用されることを確認します。

索引モデルが issue の本文から書いたものです。