feat: Implement IYYJSONManager interface for external extensions (implements #6)

Add utility methods to make the interface more
convenient for external C++ extensions (WebSocket, HTTP, etc.).

Changes:
- Add new interface methods for external extensions:
  * Release(YYJSONValue*): safely release JSON value objects
  * GetHandleType(): get YYJSON handle type for cross-extension access
  * GetFromHandle(): read YYJSONValue from SourceMod handle
  * ...
- Update yyjson library to version 0.12.0

- Fix handle permissions to allow cross-extension read access:
  * Set HandleAccess_Read = 0 in extension.cpp

These improvements enable external extensions to:
- Use more concise API calls with sensible defaults
- Access JSON handles across extension boundaries
- Safely manage YYJSONValue object lifetime
- Avoid dependency on YYJSON extension internals

All changes are backward compatible. Existing code continues to work
without modification.

Author: ProjectSky

AMBuilder

@@ -9,12 +9,14 @@ for cxx in builder.targets:
 
   binary.sources += [
     'src/extension.cpp',
+    'src/YYJSONManager.cpp',
     'src/json_natives.cpp',
     os.path.join(Extension.sm_root, 'public', 'smsdk_ext.cpp'),
   ]
 
   binary.compiler.includes += [
     os.path.join(builder.sourcePath, 'src'),
+    os.path.join(builder.sourcePath, 'public'),
     os.path.join(builder.sourcePath, 'third_party', 'yyjson'),
   ]
 

README.md

@@ -12,6 +12,7 @@ A [SourceMod](http://www.sourcemod.net/) extension that provides comprehensive J
 * Array and object sorting support
 * Iteration methods for arrays and objects
 * Support for both mutable and immutable JSON documents
+* Support SourceMod Extension API
 
 ## Performance
 Performance test results using [twitter.json](https://github.com/ibireme/yyjson_benchmark/blob/master/data/json/twitter.json) (0.60 MB):
@@ -60,6 +61,30 @@ ambuild
 * [API Reference](https://github.com/ProjectSky/sm-ext-yyjson/blob/main/scripting/include/yyjson.inc)
 * [Latest Release](https://github.com/ProjectSky/sm-ext-yyjson/releases)
 
+### SourceMod Extension API
+```cpp
+#include <IYYJSONManager.h>
+
+IYYJSONManager* g_pYYJSONManager = nullptr;
+
+void Ext::SDK_OnAllLoaded()
+{
+  SM_GET_LATE_IFACE(YYJSONMANAGER, g_pYYJSONManager);
+
+  char error[256];
+  YYJSONValue* val = g_pYYJSONManager->ParseJSON("{\"name\":\"John\", \"age\":30}", false, false, 0, error, sizeof(error));
+
+  size_t size = g_pYYJSONManager->GetSerializedSize(val);
+  char buffer[size];
+  g_pYYJSONManager->WriteToString(val, buffer, size);
+
+  // must release the value after using
+  g_pYYJSONManager->Release(val);
+
+  printf("JSON: %s\n", buffer);
+}
+```
+
 ### Basic Examples
 
 #### Working with Objects
@@ -273,7 +298,7 @@ delete obj;
 ```cpp
 // Create object from key-value string arrays
 char pairs[][] = {"name", "test", "type", "demo", "version", "1.0.0"};
-	
+  
 YYJSONObject obj = YYJSONObject.FromStrings(pairs, sizeof(pairs));
 
 /* Output: