feat(form-core): add onDynamicListenTo validator option

[jiji-hoon96]

Adds support for onDynamicListenTo to enable cross-field dynamic validation.

Changes

• Added onDynamicListenTo to FieldValidators interface
• Implemented dynamic cause handling in getLinkedFields method
• Added unit tests for both sync and async scenarios

// Password confirmation with cross-field validation
<form.Field
  name="confirmPassword"
  validators={{
    onDynamicListenTo: ['password'],  // ← Listen to password changes
    onDynamic: ({ value, fieldApi }) => {
      const password = fieldApi.form.getFieldValue('password')
      return value !== password ? 'Passwords must match' : undefined
    },
  }}
/>

Fixes #1698

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Latest commit: 5f7b420

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---

☁️ Nx Cloud last updated this comment at 2025-12-03 01:59:42 UTC

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commit: 5f7b420

[codecov]

Codecov Report

❌ Patch coverage is 94.28571% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.78%. Comparing base (6892ed0) to head (5f7b420).
⚠️ Report is 79 commits behind head on main.

Files with missing lines	Patch %	Lines
packages/form-core/src/FieldApi.ts	93.54%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1896      +/-   ##
==========================================
- Coverage   90.35%   89.78%   -0.57%     
==========================================
  Files          38       46       +8     
  Lines        1752     1939     +187     
  Branches      444      490      +46     
==========================================
+ Hits         1583     1741     +158     
- Misses        149      177      +28     
- Partials       20       21       +1     

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