Refactor type inference for collections

The type inference for collections (tuples, vectors, matrices, and
records) has been significantly refactored.

This includes:
- Introducing distinct `StaticType` variants for `Tuple`, `Vector`, and
  `Matrix`.
- Implementing more robust type checking for these collections, allowing
  for homogeneous and heterogeneous structures.
- Enhancing the `is_assignable_from` method to handle type compatibility
  between these collection types.
- Updating `Value::static_type()` to correctly infer the types of
  literal collections.
- Improving the type inference for map literals to create `Record`
  types.
- Adding comprehensive unit tests for tuple, vector, matrix, and record
  type inference.

src/ast/lexer.rs

@@ -102,12 +102,11 @@ impl<'a> Lexer<'a> {
 
     fn skip_whitespace(&mut self) {
         while let Some(&c) = self.peek() {
-            if c.is_whitespace() || is_invisible(c) {
+            if c.is_whitespace() || is_invisible(c) || c == ',' {
                 if c == '\n' {
                     self.line += 1;
                     self.col = 1;
-                } else if !is_invisible(c) {
-                    // Only increment column for characters that actually take space
+                } else {
                     self.col += 1;
                 }
                 self.input.next();