…s in templates

We extract the identifier name from the `foreignImports` expression in
`ComponentDecoratorHandler` and use a `SelectorlessMatcher` to match element
tags against these names. If an element matches both a regular Angular
directive and a foreign component, a conflict error is thrown.

In addition, we implement strict template semantic validation for these matched
foreign components within `TemplateSemanticsChecker`. Elements matched as
foreign components only support static attributes and property bindings. Any
event bindings, template references, or non-property input bindings (e.g.
class, style, or attribute bindings) trigger a semantic error diagnostic.

Finally, we skip standard DOM schema checks for foreign components to prevent spurious
validation errors since foreign components are not defined in standard HTML schemas.

When a template element matches an imported foreign component, the compiler
omits standard element instructions (`ɵɵelementStart`/`ɵɵelement`) and instead
generates a single `ɵɵforeignComponent` call. The call passes the exact foreign
import wrapper expression defined in `@Component.foreignImports` along with an
aggregated object literal containing all static attributes and property
bindings.

The instruction itself is currently a no-op.