feat(cli): detect src/ entry-point in Joomla package sub-extensions

When building a Joomla package, sub-package directories that contain a
src/ folder with a Joomla manifest XML (e.g. git submodules of full
repos) now zip src/ instead of the repo root. This avoids bundling
README, CI config, and other repo-level files into extension packages.

Authored-by: Moko Consulting
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

cli/release_package.php

@@ -230,12 +230,31 @@ class ReleasePackageCli extends CliFramework
                 $subName = basename($pkgDir);
                 $subZipPath = "{$outputDir}/{$subName}.zip";
 
+                // If sub-package is a full repo checkout (e.g. git submodule),
+                // look for a src/ subdirectory containing a Joomla manifest XML
+                // and zip that instead of the repo root.
+                $subSourceDir = $pkgDir;
+                $srcCandidate = "{$pkgDir}/src";
+                if (is_dir($srcCandidate)) {
+                    $srcManifests = array_merge(
+                        glob("{$srcCandidate}/*.xml") ?: [],
+                        glob("{$srcCandidate}/pkg_*.xml") ?: []
+                    );
+                    foreach ($srcManifests as $mf) {
+                        if (strpos(file_get_contents($mf) ?: '', '<extension') !== false) {
+                            $subSourceDir = $srcCandidate;
+                            echo "  Sub-package {$subName}: using src/ entry-point\n";
+                            break;
+                        }
+                    }
+                }
+
                 $subZip = new \ZipArchive();
                 if ($subZip->open($subZipPath, \ZipArchive::CREATE | \ZipArchive::OVERWRITE) !== true) {
                     $this->log('ERROR', "Failed to create sub-package ZIP: {$subZipPath}");
                     continue;
                 }
-                $this->addDirToZip($subZip, $pkgDir, '', $this->excludePatterns);
+                $this->addDirToZip($subZip, $subSourceDir, '', $this->excludePatterns);
                 $subZip->close();
 
                 $zip->addFile($subZipPath, "packages/{$subName}.zip");