Leptos feature wiring cleanup

[steveej]

Summary

• Stop forcing leptos/ssr + leptos/csr in workspace dependencies
• Add explicit csr features to radix-leptos crates

Motivation

• Prevent hydrate builds from pulling in SSR
• Let downstreams pick SSR/hydrate/CSR explicitly

Usage

radix-leptos = { version = "0.9.0", default-features = false, features = ["csr"] }
# or
radix-leptos = { version = "0.9.0", default-features = false, features = ["hydrate"] }
# or
radix-leptos = { version = "0.9.0", default-features = false, features = ["ssr"] }

Description

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Fixes # (issue)

Type of change

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• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Performance improvement
• Refactoring (no functional changes)

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration.

• Unit tests
• Integration tests
• Manual testing in browser
• Accessibility testing

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

Screenshots (if applicable)

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Additional Notes

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