feat(signals): add ability to provide SignalStore at the platform level

[MillerSvt]

PR Checklist

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• 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)
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PR Type

What kind of change does this PR introduce?

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

What is the current behavior?

Cannot pass any providedIn except root.

Closes #4963

What is the new behavior?

Added support to any not deprecated providedIn types.

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

I was thinking of just adding the platform to the union. But it seems that if here we just pass the value into the Injectable decorator, then we should rely on the typing of this decorator. The only thing seems to be that we should exclude deprecated types from union, so as not to add support for what will be removed soon.

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[timdeschryver]

Thanks @MillerSvt