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

src/lib/electron/electron_relay.ts

@@ -64,11 +64,68 @@ export async function launch_from_cache({
     hash,
     temp_root,
     filename,
-    hash_prefix_length = 2
-}: any) {
+    hash_prefix_length = 2,
+    script_template = null
+}: {
+    cache_root: string;
+    hash: string;
+    temp_root: string;
+    filename: string;
+    hash_prefix_length?: number;
+    /**
+     * Optional data-driven launch script. If provided, Electron runs this instead of
+     * its hardcoded extension-based logic — no app rebuild needed for script changes.
+     *
+     * Two formats:
+     *   - AppleScript: multi-line string with {{path}} placeholder (macOS only)
+     *   - Shell command: prefix with "shell:" → e.g. "shell:open \"{{path}}\""
+     *
+     * Configure via event_device.data_json.launch_scripts or $events_loc.launcher.launch_scripts.
+     * If null, Electron falls through to its built-in hardcoded defaults.
+     */
+    script_template?: string | null;
+}) {
     if (!native)
         return { success: false, error: 'Native bridge not available' };
     return await native.launch_from_cache({
+        cache_root,
+        hash,
+        temp_root,
+        filename,
+        hash_prefix_length,
+        script_template
+    });
+}
+
+/**
+ * Thin cache primitive — copies a cached file to the temp directory and returns
+ * the resolved path. The caller decides what happens next.
+ *
+ * Preferred building block for composable launch flows on the Svelte side:
+ *   1. copy_from_cache_to_temp(...)  → { path }
+ *   2. run_osascript(template.replace('{{path}}', path))
+ *      OR run_cmd(`open "${path}"`)
+ *      OR whatever you need
+ *
+ * Use launch_from_cache when the built-in hardcoded logic is sufficient.
+ * Use this when you want full control over what happens after the file lands in temp.
+ */
+export async function copy_from_cache_to_temp({
+    cache_root,
+    hash,
+    temp_root,
+    filename,
+    hash_prefix_length = 2
+}: {
+    cache_root: string;
+    hash: string;
+    temp_root: string;
+    filename: string;
+    hash_prefix_length?: number;
+}): Promise<{ success: boolean; path?: string; error?: string }> {
+    if (!native)
+        return { success: false, error: 'Native bridge not available' };
+    return await native.copy_from_cache_to_temp({
         cache_root,
         hash,
         temp_root,
@@ -129,6 +186,18 @@ export async function cleanup_tmp_files({
     return await native.run_cmd({ cmd, timeout: 30000, return_stdout: false });
 }
 
+/**
+ * Executes an AppleScript string. macOS only.
+ *
+ * HARDENED (2026-05-11): The Electron handler now writes the script to a temp .scpt
+ * file and runs `osascript "/path/to/file.scpt"` rather than passing it inline via
+ * the -e flag. This means:
+ *   - Multi-line scripts work correctly
+ *   - Paths with spaces or special characters work correctly
+ *   - No shell escaping required in the script string you pass here
+ *
+ * The .scpt file is deleted immediately after execution.
+ */
 export async function run_osascript(script: string) {
     if (!native)
         return { success: false, error: 'Native bridge not available' };