working on documentation and more API functions

site/doc/pages/component_render.txt

@@ -3,6 +3,10 @@ void component_render(String name, [DTree props], [Request& context])
 
 :see
 >ob
+component
+component_exists
+component_resolve
+1_COMPONENT
 
 :content
 Renders another `.uce` file as a component and writes the result directly to the current output buffer.
@@ -13,6 +17,8 @@ Component props are passed through `context.props`, and `name:COMPONENTFUNC` may
 
 When `name` starts with `:`, the runtime resolves that named handler against the current `.uce` file.
 
+If the target file defines `ONCE(Request& context)`, that hook runs once per request before the file's first component or render entrypoint.
+
 Use `component_render()` when you want to write component output directly from C++ code instead of capturing it as a `String`.
 
 ## Example