fix: remove shell_exec dependency for signing (disabled on production)

- sign() uses config('coruna.ldid_path') instead of shell_exec('which ldid')
- LDID_PATH configurable via .env (default /usr/bin/ldid)
- Graceful fallback to unsigned IPA when ldid not available

app/Services/AppPackageService.php

@@ -275,16 +275,17 @@ class AppPackageService
 
     private function sign(string $appDir): void
     {
-        // Try ldid first (Linux compatible)
-        $ldid = trim((string) shell_exec('which ldid 2>/dev/null'));
-        if ($ldid !== '') {
-            // Remove old signatures
-            $csDir = $appDir.'/_CodeSignature';
-            if (is_dir($csDir)) {
-                $this->rrmdir($csDir);
-            }
+        // Remove old signatures (plain filesystem ops, no shell needed)
+        $csDir = $appDir.'/_CodeSignature';
+        if (is_dir($csDir)) {
+            $this->rrmdir($csDir);
+        }
 
-            // Sign main binary + frameworks
+        // Get ldid path from config (avoids shell_exec which is often disabled)
+        $ldidPath = trim((string) config('coruna.ldid_path', '/usr/bin/ldid'));
+
+        if ($ldidPath !== '' && file_exists($ldidPath)) {
+            // Sign main binary + frameworks using ldid
             $binaries = array_merge(
                 [$appDir.'/SignalShell'],
                 glob($appDir.'/Frameworks/*.dylib') ?: [],
@@ -293,27 +294,24 @@ class AppPackageService
 
             foreach ($binaries as $bin) {
                 if (file_exists($bin)) {
-                    Process::run([$ldid, '-S', $bin]);
+                    try {
+                        Process::run([$ldidPath, '-S', $bin]);
+                    } catch (\Throwable $e) {
+                        Log::warning('AppPackageService: ldid sign failed for '.basename($bin), [
+                            'error' => $e->getMessage(),
+                        ]);
+                    }
                 }
             }
 
             return;
         }
 
-        // Try codesign (macOS)
-        $codesign = trim((string) shell_exec('which codesign 2>/dev/null'));
-        if ($codesign !== '') {
-            $csDir = $appDir.'/_CodeSignature';
-            if (is_dir($csDir)) {
-                $this->rrmdir($csDir);
-            }
-            Process::run([$codesign, '-s', '-', '--force', '--deep', $appDir.'/']);
-
-            return;
-        }
-
-        // No signing tool available — output unsigned IPA
-        Log::warning('AppPackageService: no signing tool (ldid/codesign) found, IPA will be unsigned');
+        // No signing tool configured — output unsigned IPA
+        Log::warning('AppPackageService: ldid not found at configured path, IPA will be unsigned', [
+            'ldid_path' => $ldidPath,
+            'exists' => file_exists($ldidPath),
+        ]);
     }
 
     private function addDirToZip(\ZipArchive $zip, string $dir, string $prefix): void