feat(@angular/build): subresource integrity validation for dynamically loaded modules

Adds support for verifying the integrity of dynamically loaded sub-resources by generating and pre-pending an import map with integrity hashes in the index.html

Closes #30724

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Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
style: Fix lint issues

test: Fix missing lazy modules resulting in test failures

test: Adjust test to validate more specific assumptions

fix: Escape < in generated importmap JSON

style: fix all formatting issues in angular-build

refactor: Inject importmap after base tag

fix: Lint failures in tests