fix: handle child layouts

[caalador]

Handle child layouts depending on if they have flowLayout true or false. Fixes all layouts having flowLayout if the parent layout or one child has flowLayout true.

Fixes vaadin/flow#20261

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 90.47619% with 2 lines in your changes missing coverage. Please review.

Project coverage is 92.63%. Comparing base (37ba04c) to head (df25372). Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...e-router/src/runtime/RouterConfigurationBuilder.ts	90.47%	2 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #2853 +/- ## ========================================== - Coverage 92.65% 92.63% -0.02% ========================================== Files 83 83 Lines 2831 2839 +8 Branches 729 740 +11 ========================================== + Hits 2623 2630 +7 - Misses 156 158 +2 + Partials 52 51 -1 ``` | [Flag](https://app.codecov.io/gh/vaadin/hilla/pull/2853/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=vaadin) | Coverage Δ | | |---|---|---| | [unittests](https://app.codecov.io/gh/vaadin/hilla/pull/2853/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=vaadin) | `92.63% <90.47%> (-0.02%)` | :arrow_down: | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=vaadin#carryforward-flags-in-the-pull-request-comment) to find out more.

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[mshabarov]

@platosha could you or someone else from Hilla team please review this pull request before we lost the memories what the topic was about 😄

[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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