build: update cross-repo angular dependencies to v21.2.0 (21.2.x)

[angular-robot]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
@angular-devkit/build-angular	21.2.0-rc.2 → 21.2.0
@angular-devkit/core	21.2.0-rc.2 → 21.2.0
@angular-devkit/schematics	21.2.0-rc.2 → 21.2.0
@angular/build	21.2.0-rc.2 → 21.2.0
@angular/cli	21.2.0-rc.2 → 21.2.0
@angular/ssr	21.2.0-rc.2 → 21.2.0
@schematics/angular	21.2.0-rc.2 → 21.2.0

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Release Notes

angular/angular-cli (@​angular-devkit/build-angular)

v21.2.0

Compare Source

@​angular/cli

Commit	Type	Description
0dd04f289	feat	add markdown files to Prettier's formatting list
fbae1b6ab	feat	automatic formatting files modified by schematics
91b9d281f	feat	integrate file formatting into update migrations
98a24d040	feat	standardize MCP tools around workspace/project options
d9cd609c5	fix	correctly parse scoped packages in yarn classic list output
5b05f2500	fix	enable shell option for Prettier execution on Windows platforms
25b8a157d	fix	quote complex range specifiers in package manager
6f29a8c35	fix	renamed files by their new path in the schematic workflow
201a036f2	fix	simplify Angular version compatibility checks and add special handling for local builds of new major versions
cdd26bb66	fix	validate package manager version using semver.valid and throw an error if invalid
bc363af8b	perf	optimize package manager discovery with stat-based probing

@​schematics/angular

Commit	Type	Description
aa7381efd	feat	add a '.prettierrc' file to generated workspaces and add Prettier as dev dependency
f80db6fb7	feat	add ng-add support for Vitest browser providers
5d1df50d8	fix	add actionable feedback to vitest-browser schematic

@​angular/build

Commit	Type	Description
ece30f235	feat	add headless option to unit-test builder
cad7a7c0f	feat	run vitest browser with playwright with OS theme
0b4982720	fix	adjust sourcemap sources when Vitest wrapper is bypassed
1f114a9e8	fix	bundle setup files in unit-test builder for Vitest
fd5cb28c8	fix	explicitly fail when using Vitest runtime mocking
dc899e8a5	fix	normalize allowedHosts in dev-server
26bbea12f	fix	serve extensionless assets without transformation

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[thePunderWoman]

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

• 21.2.x: c960a6e

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