refactor(audit): type-safe enums, expanded coverage, and crash-safe logging

Replace magic strings with AuditAction/AuditStatus enums across all consumers,
add logAuditWithCurrentUser() convenience wrapper, extend audit coverage to
data import, result export, app update, and ERP credentials operations, and
harden crash handlers with try/catch to prevent audit failures from cascading.

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

tests/unit/mysql.test.ts

@@ -132,7 +132,10 @@ describe('MySqlService Unit Tests', () => {
     it('should execute SELECT and return rows with columns', async () => {
       await service.connect()
       mockExecute.mockResolvedValue([
-        [{ id: 1, name: 'test' }, { id: 2, name: 'foo' }],
+        [
+          { id: 1, name: 'test' },
+          { id: 2, name: 'foo' }
+        ],
         [{ name: 'id' }, { name: 'name' }]
       ])