Reorganize top-level directories with clearer naming convention

app -> app-desktop-macos, presets -> app-presets, server -> remote-server,
daw-config-reaper -> osc-config-daw, plugin-reaper-realearn -> plugin-reaper-relearn.
Updated run.py and presets.py path references accordingly.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

plugin-reaper-relearn/macros/src/lib.rs

@@ -0,0 +1,2 @@
+#[macro_use]
+mod reaper_api;

plugin-reaper-relearn/macros/src/reaper_api.rs

@@ -0,0 +1,81 @@
+#[macro_export]
+macro_rules! reaper_api {
+    (
+        $trait_name:ident, $pointer_struct_name:ident, $session_struct_name:ident, $reg_func_name:ident
+        {
+            $(
+                $( #[doc = $doc:expr] )*
+                $func_name:ident ($( $param_name:ident: $param_type:ty ),*) $( -> $ret_type:ty )?;
+            )+
+        }
+    ) => {
+        #[derive(Default)]
+        pub struct $pointer_struct_name {
+            $(
+                $func_name: Option<fn($( $param_name: $param_type ),*) $( -> $ret_type )?>
+            ),+
+        }
+
+        impl $pointer_struct_name {
+            pub fn load(plugin_context: &reaper_low::PluginContext) -> Option<Self> {
+                let mut pointers = Self::default();
+                let mut load_count = 0;
+                unsafe {
+                    $(
+                        pointers.$func_name = std::mem::transmute(plugin_context.GetFunc(
+                            concat!(stringify!($func_name), "\0").as_ptr() as *const std::ffi::c_char,
+                        ));
+                        if pointers.$func_name.is_some() {
+                            load_count += 1;
+                        }
+                    )+
+                }
+                if load_count == 0 {
+                    return None;
+                }
+                Some(pointers)
+            }
+        }
+
+        pub struct $session_struct_name {
+            pointers: $pointer_struct_name,
+        }
+
+        impl $session_struct_name {
+            pub fn load(plugin_context: &reaper_low::PluginContext) -> Option<Self> {
+                $pointer_struct_name::load(plugin_context).map(Self::new)
+            }
+
+            pub fn new(pointers: $pointer_struct_name) -> Self {
+                Self {
+                    pointers
+                }
+            }
+
+            $(
+                $( #[doc = $doc] )*
+                pub fn $func_name(&self, $( $param_name: $param_type ),*) $( -> $ret_type )? {
+                    self.pointers.$func_name.unwrap()($( $param_name ),*)
+                }
+            )+
+        }
+
+        pub trait $trait_name {
+            $(
+                extern "C" fn $func_name($( $param_name: $param_type ),*) $( -> $ret_type )?;
+            )+
+        }
+
+        pub fn $reg_func_name<T: $trait_name, E>(mut register_api_fn: impl FnMut(&std::ffi::CStr, *mut std::ffi::c_void) -> Result<(), E> ) -> Result<(), E> {
+            unsafe {
+                $(
+                    register_api_fn(
+                        std::ffi::CStr::from_ptr(concat!(stringify!($func_name), "\0").as_ptr() as *const std::ffi::c_char),
+                        T::$func_name as *mut std::ffi::c_void,
+                    )?;
+                )+
+            }
+            Ok(())
+        }
+    };
+}