[Feat] (MG_Impl, MG_Backend): implement the integer direct state access framebuffer clears

glClearNamedFramebufferiv and glClearNamedFramebufferuiv were stubs, so a clear through
them was silently dropped and the attachment kept whatever it held. Their float siblings
were already implemented, which is what made the gap look like a rendering bug rather than
a missing entry point.

Which buffers they accept is narrower than glClearNamedFramebufferfv and differs between
the two: signed values clear COLOR or STENCIL, unsigned only COLOR (GL 4.6 core 17.4.3.1).
Only the colour buffer is indexed, so a stencil clear naming any drawbuffer other than 0 is
INVALID_VALUE rather than merely ignored, and anything else is INVALID_ENUM. Resolving the
framebuffer by name goes through the same helper the float forms use, which is what reports
INVALID_OPERATION for a name that is neither zero nor an existing framebuffer.

Both backends express them the way they already express the float forms: DirectGLES binds
the named framebuffer and forwards to glClearBuffer*, Magma queues the payload against the
named framebuffer rather than the bound one.

direct_state_access.framebuffers_clear_errors passes on both backends, and
framebuffers_clear passes on Espryt. Magma still fails that one, for a separate reason on
the materialization side rather than in these entry points.

MobileGL/MG_Backend/DirectGLES/BackendObject_DirectGLES.cpp

@@ -988,6 +988,8 @@ namespace MobileGL::MG_Backend::DirectGLES {
             funcsTable.GL.ClearBufferuiv = ClearBufferuiv;
             funcsTable.GL.ClearBufferiv = ClearBufferiv;
             funcsTable.GL.ClearNamedFramebufferfv = ClearNamedFramebufferfv;
+            funcsTable.GL.ClearNamedFramebufferiv = ClearNamedFramebufferiv;
+            funcsTable.GL.ClearNamedFramebufferuiv = ClearNamedFramebufferuiv;
             funcsTable.GL.ClearNamedFramebufferfi = ClearNamedFramebufferfi;
             funcsTable.GL.BlitFramebuffer = BlitFramebuffer;
             funcsTable.GL.BlitNamedFramebuffer = BlitNamedFramebuffer;

MobileGL/MG_Backend/DirectGLES/DirectGLES.cpp

@@ -4431,6 +4431,40 @@ namespace MobileGL::MG_Backend::DirectGLES {
         ForceBindCurrentFBO(FramebufferTarget::Draw);
     }
 
+    void ClearNamedFramebufferiv(const SharedPtr<MG_State::GLState::FramebufferObject>& framebuffer,
+                                 GLenum buffer, GLint drawbuffer, const GLint* value) {
+#if MOBILEGL_LOG_ACTIVE_LEVEL <= MOBILEGL_LOG_LEVEL_DEBUG && MOBILEGL_ENABLE_SCOPE_MARKER
+        DebugImpl::OpenGLScopeMarker marker(__func__);
+#endif
+        TextureImpl::SyncNeccessaryTextures();
+        RenderStateImpl::SyncRenderState();
+
+        SyncAndBindFramebufferObject(framebuffer, FramebufferTarget::Draw, true);
+        g_GLESFuncs.glClearBufferiv(buffer, drawbuffer, value);
+        DebugImpl::ErrorLopper::Loop([file = __FILE__, line = __LINE__](auto err) {
+            MGLOG_D("ES error (%s:%d): %s", file, line, MG_Util::ConvertGLEnumToString(err).c_str());
+        });
+
+        ForceBindCurrentFBO(FramebufferTarget::Draw);
+    }
+
+    void ClearNamedFramebufferuiv(const SharedPtr<MG_State::GLState::FramebufferObject>& framebuffer,
+                                  GLenum buffer, GLint drawbuffer, const GLuint* value) {
+#if MOBILEGL_LOG_ACTIVE_LEVEL <= MOBILEGL_LOG_LEVEL_DEBUG && MOBILEGL_ENABLE_SCOPE_MARKER
+        DebugImpl::OpenGLScopeMarker marker(__func__);
+#endif
+        TextureImpl::SyncNeccessaryTextures();
+        RenderStateImpl::SyncRenderState();
+
+        SyncAndBindFramebufferObject(framebuffer, FramebufferTarget::Draw, true);
+        g_GLESFuncs.glClearBufferuiv(buffer, drawbuffer, value);
+        DebugImpl::ErrorLopper::Loop([file = __FILE__, line = __LINE__](auto err) {
+            MGLOG_D("ES error (%s:%d): %s", file, line, MG_Util::ConvertGLEnumToString(err).c_str());
+        });
+
+        ForceBindCurrentFBO(FramebufferTarget::Draw);
+    }
+
     static SizeT AlignPixelRow(SizeT rowBytes, Int alignment) {
         const SizeT resolvedAlignment = static_cast<SizeT>(std::max(alignment, 1));
         return (rowBytes + resolvedAlignment - 1) & ~(resolvedAlignment - 1);

MobileGL/MG_Backend/DirectGLES/DirectGLES.h

@@ -59,6 +59,10 @@ namespace MobileGL::MG_Backend::DirectGLES {
                                  GLenum buffer, GLint drawbuffer, const GLfloat* value);
     void ClearNamedFramebufferfi(const SharedPtr<MG_State::GLState::FramebufferObject>& framebuffer,
                                  GLenum buffer, GLint drawbuffer, GLfloat depth, GLint stencil);
+    void ClearNamedFramebufferiv(const SharedPtr<MG_State::GLState::FramebufferObject>& framebuffer,
+                                 GLenum buffer, GLint drawbuffer, const GLint* value);
+    void ClearNamedFramebufferuiv(const SharedPtr<MG_State::GLState::FramebufferObject>& framebuffer,
+                                  GLenum buffer, GLint drawbuffer, const GLuint* value);
     void BlitFramebuffer(GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1, GLint dstX0, GLint dstY0, GLint dstX1,
                          GLint dstY1, GLbitfield mask, GLenum filter);
     void BlitNamedFramebuffer(const SharedPtr<MG_State::GLState::FramebufferObject>& readFramebuffer,