fix: tableFromJSON and tableFromArrays crash on arrays of strings

[kentkwu]

What's Changed

Applies a fix for type inference crashing on encountering an array of strings.

Added a compareTypesForInference helper that compares Dictionary types structurally, ignoring IDs. It recurses through List and Struct for nested cases. The public compareTypes is unchanged. ID equality still matters for IPC comparisons.

Root cause:

Strings infer to Dictionary<Utf8, Int32>, and every Dictionary construction auto-increments a global ID. The array homogeneity check in inferType calls compareTypes on separately inferred types, which requires matching IDs — so it always fails for string arrays.

Closes #86, #50

[kou]

@matheuzinoficial @hemkumarrao-ni @knight556 Could you try this fix?

[Copilot]

Pull request overview

Fixes tableFromJSON() / tableFromArrays() type inference crashes when encountering arrays of strings by comparing inferred types structurally (ignoring Dictionary IDs that auto-increment per construction), including nested List and Struct cases.

Changes:

• Added an internal compareTypesForInference() helper to compare Dictionary types without requiring matching IDs, with recursion for List and Struct.
• Updated list homogeneity checking in inferType() to use the new inference comparator.
• Added unit tests covering arrays of strings and nested objects containing strings for both tableFromArrays() and tableFromJSON().

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/factories.ts	Introduces ID-agnostic type comparison for inference and applies it to list inference checks to prevent false mismatches for string dictionaries.
test/unit/table/table-test.ts	Adds regression tests demonstrating correct behavior for string arrays and nested string-containing structures.

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[trxcllnt]

What if we just passed the dictionaryId down through inferType? e.g.

Suggested change

	if (array.every((ary) => ary == null || compareTypesForInference(childType, inferType(ary)))) {
	if (array.every((ary) => ary == null || compareTypes(childType, inferType(ary, dtypes.DataType.isDictionary(childType) ? childType.id : null)))) {

Then we could pass the dictionary id into the Dictionary constructor on L142?

[trxcllnt]

Would probably need to maintain a Map of key -> dictionary id in order to do the same thing for dictionary-encoded struct children.

[trxcllnt]

Left a comment with a suggestion, curious to hear your thoughts.