build: enable strict mode

[timdeschryver]

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/ngrx/platform/blob/main/CONTRIBUTING.md#commit
• Tests for the changes have been added (for bug fixes / features)
• Documentation has been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[ ] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[x] Build related changes
[ ] CI related changes
[ ] Documentation content changes
[ ] Other... Please describe:

What is the current behavior?

Packages have their own isolated tsconfig.build files.

What is the new behavior?

• Strict mode is enabled while building
• Each tsconfig.build.json file extends from a base class.

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

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[timdeschryver]

We might want to enable this in a feature release for all packages (currently only signals and operators).
useDefineForClassFields is the new standard (with ES2022).

But this will be some work #3654