fix: add validation for edge expressions

[doc-han]

Description

This PR add validation for edge expressions when you switch the condition to it. makes sure to show an error when its blank.

Closes #3704

Validation steps

1. Pick an edge
2. switch to "Match a Javascript Expression"
3. If it's empty, then expect an error form validation to be shown below the input in red.
4. If it's not empty, try emptying it and expect the same outcome.

Additional notes for the reviewer

1. (Is there anything else the reviewer should know or look out for?)

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.80%. Comparing base (0d86986) to head (c6c681c).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4009      +/-   ##
==========================================
+ Coverage   88.76%   88.80%   +0.04%     
==========================================
  Files         422      422              
  Lines       19106    19106              
==========================================
+ Hits        16959    16968       +9     
+ Misses       2147     2138       -9     

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[doc-han]

While working on this. spotted some wrong behaviours in the coloring of edges red based on the errors they were facing.
something not clear in the below code.

lightning/assets/js/collaborative-editor/hooks/useValidation.ts

Lines 79 to 108 in 9cad92e

	Object.keys(formState.values).forEach(fieldName => {
	const fieldMeta = form.getFieldMeta(fieldName);
	// Only include fields that have been touched/interacted with
	// This preserves server errors for untouched fields
	if (fieldMeta?.isTouched || fieldMeta?.isDirty) {
	// Get client validation errors (exclude collaborative errors from errorMap)
	const meta = fieldMeta as unknown as Record<string, unknown>;
	const errorMap = (meta?.errorMap as Record<string, unknown>) || {};
	// Filter out collaborative errors - only send client validation errors
	const clientValidationErrors = (fieldMeta?.errors || []).filter(
	(error: unknown) => {
	// If this error matches the collaborative error, exclude it
	const collaborativeError = errorMap.collaborative;
	return error !== collaborativeError;
	}
	);
	if (clientValidationErrors.length > 0) {
	// Field has client validation errors
	clientErrors[fieldName] = clientValidationErrors.map(
	(e: unknown) => (typeof e === 'string' ? e : String(e))
	);
	} else {
	// Field is valid or only has collaborative errors - send empty array to clear
	clientErrors[fieldName] = [];
	}
	}
	});

[elias-ba]

Hey @doc-han I see 3 things that look like problems we need to address. Now I am not super sure whether this is related to this issue / pr.

1. When I type in the edge label I don't see it appear in the edge
2. When I type a valid JS Expression I don't see the error disappear; it stays
3. When I hit the save button, I see that Edges: [object Oject] in the error message.

[doc-han]

Nice catch @elias-ba
going over it once again.

[doc-han]

Several things out of scope of this PR in relation to what you raised @elias-ba.
Will spend the rest of the day on this actually.