Improve DynamicValue error handling with Validation

[AfshaZabeen-5G2]

/claim #480

🎯 Summary

This PR improves the DynamicValue.toTypedValue operation by switching from a "fail-fast" Either approach to an "error-accumulating" Validation approach using zio-prelude. This allows the library to collect all validation errors in a single pass instead of stopping at the first failure.

❓ Problem

The previous implementation used Either[DecodeError, A], which:

• Stopped conversion at the first encountered error.
• For complex nested structures, only reported the first issue found.
• Forced users into an inefficient "fix one, re-run, find the next" workflow.

✅ Solution

Implemented Validation[DecodeError, A] from zio-prelude to enable:

• Error Accumulation: Reports all validation issues across the entire data structure in one go.
• Improved DX: Developers can now see the full state of their data's validity.
• Zero Breaking Changes: Fully backward compatible with existing Either and Option APIs.

🛠 Changes

1. New API Method

def toTypedValueValidation[A](implicit schema: Schema[A]): Validation[DecodeError, A]

• The primary entry point for users who want to access accumulated errors.

2. Updated Existing Methods (Backward Compatible)

• toTypedValue[A]: Now projects Validation to Either, combining multiple errors into a single string.
• toValue[A]: Now projects Validation to Either, combining multiple errors using DecodeError.And.
• toTypedValueOption[A]: Internal logic now uses validation, but still returns None on any failure.

3. Error Accumulation Points

Errors are now collected across:

• Tuples: Both left and right errors via Validation.validateWith.
• Sequences/Sets: All element errors via Validation.validateAll.
• Maps: Both key and value errors.
• Records: All field errors via the new decodeStructureValidation.

4. Helper Methods

• DecodeError.And.reduce: Helper to merge multiple DecodeError instances.
• decodeStructureValidation: A validation-native version of the record decoding logic.

🧪 Testing & Verification

Added a new test suite: DynamicValueValidationSpec.scala.

• ✅ Accumulation Tests: Verified that multiple errors in records, maps, and sequences are all caught.
• ✅ Regression Tests: Ensured existing Either-based APIs still function as expected.
• ✅ CI Check: Ran ./sbt "testsJVM/test" and all tests passed (100%).

📋 Checklist

• Implementation follows error accumulation pattern.
• All existing APIs remain backward compatible.
• New toTypedValueValidation method added.
• Comprehensive test suite added.
• No breaking changes.
• Demo video provided (will add)

[CLAassistant]

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