build: update cross-repo angular dependencies to v21.2.0-next.1

[angular-robot]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
@angular/build	21.2.0-next.0 → 21.2.0-next.1
@angular/cli	21.2.0-next.0 → 21.2.0-next.1

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Release Notes

angular/angular-cli (@​angular/build)

v21.2.0-next.1

Compare Source

@​angular/cli

Commit	Type	Description
91b9d281f	feat	integrate file formatting into update migrations
6f29a8c35	fix	renamed files by their new path in the schematic workflow
bc363af8b	perf	optimize package manager discovery with stat-based probing

@​schematics/angular

Commit	Type	Description
5d1df50d8	fix	add actionable feedback to vitest-browser schematic
51fc77828	fix	warn when production configuration is missing for service worker

@​angular/build

Commit	Type	Description
ece30f235	feat	add headless option to unit-test builder
1f114a9e8	fix	bundle setup files in unit-test builder for Vitest

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[alan-agius4]

This PR was merged into the repository. The changes were merged into the following branches:

• main: cb6f9af