Ψ-W1-T3 review remediation: soften the double-fire claim to unspecified-by-SDK, mark the unload mirror [verify — DAW], fix stale comment, drop redundant assertions, dedupe hook-partitioning comments, drop what-comment; file the action_registry test-seam deferral.

src/app/main.cpp

@@ -230,8 +230,8 @@ static bool OnHookCommand(int command, int /*flag*/)
 }
 
 // "hookcommand" covers the main section only, so actions we published into another
-// section arrive here instead. Claim ONLY those — every main-section id stays with
-// OnHookCommand, so no command can be claimed by both hooks.
+// section arrive here instead. Partitioning contract: root `CLAUDE.md` §"REAPER
+// extension contract".
 static bool OnHookCommand2(KbdSectionInfo* /*sec*/, int command, int /*val*/, int /*val2*/,
                            int /*relmode*/, HWND /*hwnd*/)
 {

src/shell/actions/ingest.cpp

@@ -479,7 +479,7 @@ void ingestRegisterActions(reaper_plugin_info_t* rec, ReaSamplerSession* session
     g_customImportMediaExplorer.uniqueSectionId = kSectionMediaExplorer;
     g_customImportMediaExplorer.idStr           = g_idImportMxStr.c_str();
     g_customImportMediaExplorer.name            = g_labelImportStr.c_str();
-    g_customImportMediaExplorer.extra           = nullptr;  // reserved
+    g_customImportMediaExplorer.extra           = nullptr;
     g_cmdImportMediaExplorerMx =
         rec->Register("custom_action", (void*)&g_customImportMediaExplorer);
     if (!g_cmdImportMediaExplorerMx)
@@ -496,8 +496,8 @@ bool ingestHandleCommand(int command) {
 
 bool ingestHandleSectionCommand(int command) {
     if (command == 0 || !g_session) return false;
-    // ONLY the Media Explorer id. The Main entry has its own distinct id and is claimed by
-    // ingestHandleCommand off "hookcommand"; claiming it here too would double-fire it.
+    // ONLY the Media Explorer id — partitioning contract: root `CLAUDE.md`
+    // §"REAPER extension contract".
     if (command == g_cmdImportMediaExplorerMx) { doImportFromMediaExplorer(); return true; }
     return false;
 }