Module for_statement 

for loop parser - three distinct syntaxes.

rl-lang supports three for forms:

// 1. C-style: initializer, condition, increment inside brackets
for [int i = 0, i < 10, i += 1] { … }

// 2. Range iteration: integer variable over a literal range
for x in 0..10 { … }

// 3. Foreach: variable over an array variable or expression
for item in my_array { … }

The leading token after for disambiguates the form:

• [ -> C-style (StatementKind::For)
• identifier -> range or foreach (StatementKind::ForRange / StatementKind::ForEach)
• anything else -> error