Make standalone import the default

Since Angular now defaults to standalone component, it only make sense for ionic imports to be standalone by default.

It gets tedious to type something like:

```ts
import { Config } from '@ionic/angular/standalone';
```

vs

```ts
import { Config } from '@ionic/angular/';
```

Make NgModule based apps use:

```ts
import { Config } from '@ionic/angular/ngmodule';
```

Start by tracing how the Ionic CLI exposes or generates Angular imports, then compare the standalone and NgModule entry points shown in the issue. No source file, test, or entry point is named in the payload, so identify the relevant import-resolution and project-generation code first. Done means standalone imports work by default while NgModule apps use the explicit @ionic/angular/ngmodule path, with tests covering both modes.

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