build: update cross-repo angular dependencies to v21.0.6 (21.0.x)

[angular-robot]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
@angular/common (source)	21.0.5 -> 21.0.6
@angular/compiler (source)	21.0.5 -> 21.0.6
@angular/compiler-cli (source)	21.0.5 -> 21.0.6
@angular/core (source)	21.0.5 -> 21.0.6
@angular/forms (source)	21.0.5 -> 21.0.6
@angular/localize	21.0.5 -> 21.0.6
@angular/platform-browser (source)	21.0.5 -> 21.0.6
@angular/platform-browser-dynamic (source)	21.0.5 -> 21.0.6
@angular/platform-server (source)	21.0.5 -> 21.0.6
@angular/router (source)	21.0.5 -> 21.0.6

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Release Notes

angular/angular (@​angular/common)

v21.0.6

Compare Source

Breaking Changes (affecting only experimental features)

forms

• The shape of SignalFormsConfig.classes has changed

  Previously each function in the classes map took a FieldState. Now
  it takes a Field directive.

  For example if you previously had:

  provideSignalFormsConfig({
    classes: {
      'my-valid': (state) => state.valid()
    }
  })
  

  You would need to update to:

  provideSignalFormsConfig({
    classes: {
      'my-valid': ({state}) => state().valid()
    }
  })
  

  (cherry picked from commit 348f149)

• (cherry picked from commit ae0c590)

core

Commit	Type	Description
4c8fb3631d	fix	throw better errors for potential circular references
48492524ea	fix	use mutable ResponseInit type for RESPONSE_INIT token

forms

Commit	Type	Description
81772b420d	feat	pass field directive to class config
729b96476b	refactor	rename field to fieldTree in FieldContext and ValidationError

language-service

Commit	Type	Description
e0694df3ec	fix	avoid interpolation highlighting inside @​let
5047be4bc1	fix	Prevent language service from crashing on suggestion diagnostic errors

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