Fix ESLint errors, bugs, and add gravity export

- Fix missing return in childRegistrationUtils.registerChild()
- Fix assertionUtils: assertNoNaN uses this.assertNoNaN
- Fix logger: nameModule uses this.nameModule
- Fix assetUtils: convert ESM to CommonJS
- Fix childRegistrationUtils_DEPRECATED: desc -> softwareType
- Add gravity export to index.js for rotatingMachine
- Fix ESLint errors across 18 files (no-undef, no-case-declarations,
  no-mixed-spaces-and-tabs, parsing errors)

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

src/helper/logger.js

@@ -44,7 +44,7 @@ class Logger {
       if (this.levels.includes(level)) {
         this.logLevel = level;
       } else {
-        console.error(`[ERROR ${nameModule}]: Invalid log level: ${level}`);
+        console.error(`[ERROR ${this.nameModule}]: Invalid log level: ${level}`);
       }
     }