bug(cdk/dialog): parent injector not working correctly

### Is this a regression?

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

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

18

### Description

Tokens from the parent injector are not available.
The behaviour is different between a ngComponentOutlet and the injector added to dialog

### Reproduction

StackBlitz link: https://stackblitz.com/edit/stackblitz-starters-epebydgb
Steps to reproduce:
1.
2.

### Expected Behavior

Tokens from the parent injector are available

### Actual Behavior

Tokens from parent injector are not available

### Environment

```
_ _ ____ _ ___
/ \ _ __ __ _ _ _| | __ _ _ __ / ___| | |_ _|
/ △ \ | '_ \ / _` | | | | |/ _` | '__| | | | | | |
/ ___ \| | | | (_| | |_| | | (_| | | | |___| |___ | |
/_/ \_\_| |_|\__, |\__,_|_|\__,_|_| \____|_____|___|
|___/

Angular CLI: 19.0.0
Node: 18.20.3
Package Manager: npm 10.2.3
OS: linux x64

Angular: 19.0.0
... animations, build, cli, common, compiler, compiler-cli, core
... forms, platform-browser, router

Package Version
------------------------------------------------------
@angular-devkit/architect 0.1900.0
@angular-devkit/core 19.0.0
@angular-devkit/schematics 19.0.0
@angular/cdk 19.0.5
@schematics/angular 19.0.0
rxjs 7.8.1
typescript 5.6.3
zone.js 0.15.0
```

Start with the linked StackBlitz reproduction and compare the parent-injector behavior of ngComponentOutlet with the injector added to cdk/dialog. Trace the relevant dialog and injector entry points shown by the reproduction. Done means tokens from the parent injector are available through the dialog as expected.

Written by the indexing model from the issue text.