fix(ui): fix rules of hooks violations via useId

[franzheidl]

-- WIP UNTESTED, DO NOT MERGE --

Summary

Fix all useId-related violations of Rules of Hooks: Call hooks only on top level

Changes Made

• CheckboxGroup — replaced uniqueId() wrapper with two top-level calls generatedName = useId() and generatedId = useId(); used inline in groupName and groupId assignments
• ComboBox — extracted generatedId = useId() to top level; split off from the conditional theId assignment; helptextId was already unconditional so unchanged
• RadioGroup — same as CheckboxGroup: two separate top-level useId() calls for generatedName and generatedId
• SecretText — removed uniqueId arrow function; replaced with top-level generatedId = useId() used in theId assignment
• Select — removed uniqueId arrow function; replaced with top-level generatedId = useId() used in theId assignment; helptextId was already unconditional so unchanged
• Switch — removed generateUniqueId arrow function; replaced with top-level generatedId = useId(); introduced theId combining id and generatedId; updated id and htmlFor usages in JSX from generatedId to theId
• TextInput — removed uniqueId arrow function; replaced with top-level generatedId = useId() used in theId assignment
• Textarea — removed uniqueId arrow function; replaced with top-level generatedId = useId() used in theId assignment

Related Issues

Closes #1589

Testing Instructions

1. pnpm i
2. pnpm run test

Checklist

• I have performed a self-review of my code.
• I have commented my code, particularly in hard-to-understand areas.
• 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.
• I have made corresponding changes to the documentation (if applicable).
• My changes generate no new warnings or errors.
• I have created a changeset for my changes.

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