fix(core): Refactor module imports to use the centralized plugins module and update relative paths across the codebase. Also remove the obsolete test file (test/test.other-formats-corpus.ts) and update file metadata in test outputs.

ts/classes.xinvoice.ts

@@ -1,4 +1,6 @@
-import { business, finance } from '@tsclass/tsclass';
+import * as plugins from './plugins.js';
+
+import { business, finance } from './plugins.js';
 import type { TInvoice } from './interfaces/common.js';
 import { InvoiceFormat, ValidationLevel } from './interfaces/common.js';
 import type { ValidationResult, ValidationError, XInvoiceOptions, IPdf, ExportFormat } from './interfaces/common.js';