refactor: simplify apk filename parsing logic

- Simplify parseApkFilename to use version delimiter split
- Update tests to match new data structure with rawEnvironment
- Remove unnecessary test cases and assertions

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

lib/apk-parser.ts

@@ -38,22 +38,11 @@ export function detectEnvironment(prefix: string, configuredTabs: string[]): { e
 
 export function parseApkFilename(filename: string, version: string): ParsedApkMetadata {
   // Use version as delimiter (with leading underscore)
-  const delimiter = `_${version}`;
-  const delimiterIndex = filename.indexOf(delimiter);
-
-  let prefix: string;
-  if (delimiterIndex > 0) {
-    prefix = filename.substring(0, delimiterIndex);
-  } else {
-    // Fallback: can't find version delimiter
-    prefix = '';
-  }
-
-  const { environment, rawEnvironment } = detectEnvironment(prefix, APK_TABS);
-
-  // Extract commit ID
-  const commitMatch = filename.match(/([a-f0-9]{7,})\.apk$/);
-  const commit = commitMatch ? commitMatch[1] : null;
+  const delimiter = `_${version}_`;
+  const filenameWithoutExt = filename.replace(/\.apk$/, '');
+  const parts = filenameWithoutExt.split(delimiter);
+  const { environment, rawEnvironment } = detectEnvironment(parts[0], APK_TABS);
+  const commit = parts[1].substring(0, 9);
 
   return {
     environment,