[type]: array type aliases don't work

[CryingN]

Describe the bug

Type alias Tokens = []string cannot accept a variable initialized with []Token{} (where Token = string), even though both have the same underlying type []string. The compiler rejects the assignment with a type mismatch error.

Reproduction Steps

v_llama_cpp/type.v:

module v_llama_cpp

pub type Token = string
pub type Tokens = []string

pub fn test(data Tokens) {
    println(data)
}

test.v:

module main

import v_llama_cpp

fn main() {
    token := "data1"
    mut tokens := []v_llama_cpp.Token{}
    tokens << token
    v_llama_cpp.test(tokens)
}

Expected Behavior

v_llama_cpp.Tokens(['data1'])

Current Behavior

test.v:13:7: error: cannot use `[]v_llama_cpp.Token` as `v_llama_cpp.Tokens` in argument 1 to `v_llama_cpp.test`
   11 |     mut tokens := []Token{}
   12 |     tokens << token
   13 |     test(tokens)
      |          ~~~~~~
   14 | }
   15 |

Possible Solution

When checking type compatibility, recursively resolve all type aliases to their fundamental types first, then compare. This aligns with the Principle of Least Astonishment and matches behavior in other statically-typed languages with type aliases. This way both []Token and Tokens normalize to []string and become compatible.

Additional Information/Context

No response

V version

[root_cn@archlinux test]$ v --version V 0.5.1 defdc5e

Environment details (OS name and version, etc.)

[root_cn@archlinux test]$ v doctor

V full version	V 0.5.1 defdc5e
OS	linux, Linux version 6.19.11-arch1-1 (linux@archlinux) (gcc (GCC) 15.2.1 20260209, GNU ld (GNU Binutils) 2.46) #1 SMP PREEMPT_DYNAMIC Thu, 02 Apr 2026 23:33:01 +0000
Processor	8 cpus, 64bit, little endian, Intel(R) Core(TM) i5-8265U CPU @ 1.60GHz
Memory	1.13GB/7.51GB
V executable	/home/root_cn/work/vlang/v/v
V last modified time	2026-04-27 07:06:52
V home dir	OK, value: /home/root_cn/work/vlang/v
VMODULES	OK, value: /home/root_cn/.vmodules
VTMP	OK, value: /tmp/v_1000
Current working dir	OK, value: /home/root_cn/work/vlang/test
Git version	git version 2.54.0
V git status	defdc5e
.git/config present	true
cc version	cc (GCC) 15.2.1 20260209
gcc version	gcc (GCC) 15.2.1 20260209
clang version	clang version 22.1.3
tcc version	tcc version 0.9.28rc 2025-02-13 HEAD@f8bd136d (x86_64 Linux)
tcc git status	thirdparty-linux-amd64 696c1d84
emcc version	N/A
glibc version	ldd (GNU libc) 2.43

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