feat(launcher): configurable launch scripts + composable native primitives

- electron_relay: type launch_from_cache with script_template param;
  add copy_from_cache_to_temp export; add JSDoc for run_osascript hardening
- launcher_file_cont: add get_launch_script_template() helper reading from
  device-level (event_device.data_json.launch_scripts) and event-level
  (events_loc.launcher.launch_scripts) config; wire into handle_open_file()
- PROJECT__AE_Events_Launcher_Native_integration.md: add Section 8
  (Configurable Launch Scripts); update IPC reference for new/changed handlers
- MODULE__AE_Events_PressMgmt_Launcher.md: add configurable launch behavior
  note to Native Mode Safe Handover section

documentation/MODULE__AE_Events_PressMgmt_Launcher.md

@@ -311,6 +311,13 @@ The Electron app zero-configs itself:
 3. Rename to original filename (e.g., `Abstract_101.pptx`)
 4. OS opens the file (Keynote, PowerPoint, Preview, etc.)
 
+**Configurable launch behavior:** The open/launch command in step 4 can be overridden
+per file extension via `event_device.data_json.launch_scripts` (device-level config) or
+`event.launcher.launch_scripts` (event-level fallback). Templates use `{{path}}` as the
+file path placeholder; AppleScript or `shell:` prefixed commands are both supported. No
+Electron rebuild required to change how files open — edit config in Aether and it applies
+immediately. See `PROJECT__AE_Events_Launcher_Native_integration.md` Section 8.
+
 Versioning is handled automatically: when a presenter uploads an updated file, the new
 hash is cached separately and the old one remains intact.