feat: Add async/await support with new IR generation and updated documentation.

Author: ProgrammerKR

README.md

@@ -251,10 +251,28 @@ use local_helper;
 
 func main() {
     let result = std.math.sqrt(16);
+
     print("Square root of 16: " + to_string(result));
 }
 ```
 
+### Async/Await
+
+ProXPL supports native asynchronous programming:
+
+```javascript
+async func fetchUser(id) {
+    // Simulate non-blocking operation
+    return {"id": id, "name": "User" + to_string(id)};
+}
+
+async func main() {
+    print("Fetching user...");
+    let user = await fetchUser(42);
+    print("Got user: " + user["name"]);
+}
+```
+
 ### Standard Library Examples
 
 ```javascript

src/compiler/ir_gen.c

@@ -6,6 +6,7 @@
 
 #include "../../include/ir.h"
 #include "../../include/ast.h"
+#include "../../include/object.h"
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>

src/compiler/parser/parser.c

@@ -16,7 +16,7 @@
 // Forward declarations of parsing functions
 static Stmt *declaration(Parser *p);
 static Stmt *statement(Parser *p);
-static Stmt *funcDecl(Parser *p, const char *kind);
+static Stmt *funcDecl(Parser *p, const char *kind, bool isAsync);
 static Stmt *classDecl(Parser *p);
 static Stmt *varDecl(Parser *p);
 static Stmt *useDecl(Parser *p);