feat(array): support Vec<(K,V)> for hashtables

Refs: #425

Author: Xenira

guide/src/types/hashmap.md

@@ -14,6 +14,17 @@ numeric key, the key is represented as a string before being inserted.
 Converting from a `HashMap` to a zval is valid when the key implements
 `AsRef<str>`, and the value implements `IntoZval`.
 
+<div class="warning">
+
+    When using `HashMap` the order of the elements it not preserved.
+
+    HashMaps are unordered collections, so the order of elements may not be the same
+    when converting from PHP to Rust and back.
+
+    If you need to preserve the order of elements, consider using `Vec<(K, V)>` or
+    `Vec<ArrayKey, V)>` instead.
+</div>
+
 ## Rust example
 
 ```rust,no_run
@@ -49,9 +60,93 @@ var_dump(test_hashmap([
 Output:
 
 ```text
-k: hello v: world
 k: rust v: php
+k: hello v: world
 k: 0 v: okk
+array(3) {
+    [0] => string(3) "php",
+    [1] => string(5) "world",
+    [2] => string(3) "okk"
+}
+```
+
+## `Vec<(K, V)>` and `Vec<ArrayKey, V>`
+
+`Vec<(K, V)>` and `Vec<ArrayKey, V>` are used to represent associative arrays in PHP
+where the keys can be strings or integers.
+
+If using `String` or `&str` as the key type, only string keys will be accepted.
+
+For `i64` keys, string keys that can be parsed as integers will be accepted, and
+converted to `i64`.
+
+If you need to accept both string and integer keys, use `ArrayKey` as the key type.
+
+### Rust example
+
+```rust,no_run
+# #![cfg_attr(windows, feature(abi_vectorcall))]
+# extern crate ext_php_rs;
+# use ext_php_rs::prelude::*;
+# use ext_php_rs::types::ArrayKey;
+#[php_function]
+pub fn test_vec_kv(vec: Vec<(String, String)>) -> Vec<String> {
+    for (k, v) in vec.iter() {
+        println!("k: {} v: {}", k, v);
+    }
+
+    vec.into_iter()
+        .map(|(_, v)| v)
+        .collect::<Vec<_>>()
+}
+
+#[php_function]
+pub fn test_vec_arraykey(vec: Vec<(ArrayKey, String)>) -> Vec<String> {
+    for (k, v) in vec.iter() {
+        println!("k: {} v: {}", k, v);
+    }
+
+    vec.into_iter()
+        .map(|(_, v)| v)
+        .collect::<Vec<_>>()
+}
+# fn main() {}
+```
+
+## PHP example
+
+```php
+<?php
+
+declare(strict_types=1);
+
+var_dump(test_vec_kv([
+    ['hello', 'world'],
+    ['rust', 'php'],
+    ['okk', 'okk'],
+]));
+
+var_dump(test_vec_arraykey([
+    ['hello', 'world'],
+    [1, 'php'],
+    ["2", 'okk'],
+]));
+```
+
+Output:
+
+```text
+k: hello v: world
+k: rust v: php
+k: okk v: okk
+array(3) {
+    [0] => string(5) "world",
+    [1] => string(3) "php",
+    [2] => string(3) "okk"
+}
+k: hello v: world
+k: 1 v: php
+k: 2 v: okk
 array(3) {
     [0] => string(5) "world",
     [1] => string(3) "php",