build: split the engine into liboakengine.so; worker drops the UI entirely

Physical split: app/{audio,cli,codec,common,config,node,pluginSupport,
render,task,timeline,undo,tool,shaders} plus coreengine, version and
ui/icons+colorcoding move to a new top-level engine/ tree, built as
liboakengine.so (shared). The render backends (oakgl/oakvulkan) move
with it and link the engine library instead of embedding a static
render-core subset (libolive-rendercore is gone).

- oak-render-worker now links liboakengine instead of the whole
  libolive-editor object set: 336MB -> 2.9MB, no Qt Widgets UI
- the editor links liboakengine for the engine and keeps only UI
  objects in libolive-editor
- install/packaging: GNUInstallDirs libdir on Linux, bundle copy on
  macOS, oakengine.dll staged for NSIS, AppImage validation entry
- fix backend lookup for the new layout: DynamicRenderer searched
  ../app but backends now live in engine/; a stale pre-split liboakgl
  in the build tree got dlopened instead, re-initialized and later
  destroyed the interposed engine statics (full-suite segfault at
  DialogSequenceParameterTab, found via gdb watchpoint)

engine/render/plugin/pluginrenderer.h

@@ -0,0 +1,85 @@
+/*
+ * Oak Video Editor - Non-Linear Video Editor
+ * Copyright (C) 2025 Olive CE Team
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+//
+// Created by mikesolar on 25-10-19.
+//
+
+#ifndef OAK_PLUGINRENDERER_H
+#define OAK_PLUGINRENDERER_H
+
+#include <QObject>
+
+#include "render/renderer.h"
+#include "render/job/pluginjob.h"
+
+namespace olive
+{
+namespace plugin
+{
+namespace detail
+{
+// 作用：将字节行跨度转换为像素跨度，便于纹理读写。
+// Purpose: Convert byte stride to pixel stride for texture I/O.
+int bytes_to_pixels(int byte_linesize, const olive::VideoParams &params);
+}
+// 作用：OFX 插件渲染器，负责 CPU/GL 路径下的插件调用和纹理桥接。
+// Purpose: OFX plugin renderer that drives CPU/GL render paths and texture bridging.
+//
+// 不再继承 OpenGLRenderer，而是持有一个通用的 Renderer 指针。这样当主渲染器
+// 是 Vulkan 或动态加载的后端时，插件仍可通过 CPU readback/upload 路径工作；
+// 仅当底层渲染器真正支持 OpenGL 时才走 OFX OpenGL 渲染路径。
+class PluginRenderer : public QObject {
+	Q_OBJECT
+public:
+	explicit PluginRenderer(olive::Renderer *renderer,
+							QObject *parent = nullptr)
+		: QObject(parent)
+		, renderer_(renderer)
+	{
+	}
+	virtual ~PluginRenderer() override
+	{
+	}
+
+	olive::Renderer *renderer() const
+	{
+		return renderer_;
+	}
+
+	// 作用：将目标纹理绑定为插件输出。
+	// Purpose: Attach destination texture as OFX output.
+	void attach_output_texture(olive::TexturePtr texture);
+	// 作用：解除目标纹理绑定。
+	// Purpose: Detach destination texture binding.
+	void detach_output_texture();
+	// 作用：执行插件渲染流程（参数配置、输入/输出、调用渲染动作）。
+	// Purpose: Execute plugin render flow (params, inputs/outputs, render actions).
+	void render_plugin(TexturePtr src, olive::plugin::PluginJob &job,
+					  olive::TexturePtr destination,
+					  olive::VideoParams destination_params,
+					  bool clear_destination, bool interactive);
+
+private:
+	olive::Renderer *renderer_;
+};
+}
+}
+
+#endif //OAK_PLUGINRENDERER_H