Add array type inference

[Ph0enixKM]

Basically we no longer need to provide an array type:

let arr = []
// ...
arr = foo() + [1] // At this point it infers the type to be `[Int]`

[Copilot]

Pull request overview

This PR adds array type inference functionality, allowing empty arrays [] to be used without explicit type annotations. The type is inferred from context such as assignments, function arguments, binary operations, and ternary expressions.

Key changes:

• Empty arrays are now parsed as generic Type::Array(Box::new(Type::Generic)) and have their types inferred from usage
• Type inference works through variable assignments, function reference parameters, binary operations, comparisons, and ternary expressions
• The update_var_type method enables updating variable types in metadata after inference

Reviewed changes

Copilot reviewed 37 out of 37 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
src/utils/metadata/parser.rs	Adds update_var_type method to update variable types during type inference
src/modules/types.rs	Updates is_subset_of to support bidirectional generic-to-concrete array type relationships and adds corresponding tests
src/modules/expression/literal/array.rs	Changes empty array parsing to create generic arrays instead of returning an error
src/modules/expression/ternop/ternary.rs	Adds type inference logic for ternary expressions and stores resolved type in new kind field
src/modules/variable/set.rs	Implements type inference for both array element assignment and full array reassignment
src/modules/shorthand/add.rs	Adds type inference when using += operator with generic arrays
src/modules/function/invocation.rs	Infers array types from function reference parameters when passing generic arrays
src/modules/expression/binop/mod.rs	Adds array type inference logic to typecheck_equality method and updates signatures to &mut
src/modules/expression/binop/*.rs	Updates all binary operators to use mutable references for type inference support
src/tests/validity/*.ab	Comprehensive test cases validating array type inference in various scenarios
src/tests/erroring/*.ab	Test cases ensuring type mismatches are properly caught after inference
src/tests/validity/modulo_num.ab	Test for modulo operation with numeric types (appears related to operator refactoring)

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