Docs: add more links to the top of every examples and backends files.

backends/imgui_impl_sdlrenderer3.cpp

@@ -12,8 +12,12 @@
 //  [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
 
 // You can copy and use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
-// If you are new to Dear ImGui, read documentation from the docs/ folder + read the top of imgui.cpp.
-// Read online: https://github.com/ocornut/imgui/tree/master/docs
+// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
 
 // CHANGELOG
 //  2023-05-30: Initial version.