Rework folder structure (#17229)

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src="https://github.com/user-attachments/assets/509b95b5-9c4f-474d-a47f-f950dee189ea"
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packages/twenty-sdk/src/cli/commands/instance/instance-upgrade.ts

@@ -0,0 +1,8 @@
+// Placeholder for instance upgrade command
+// TODO: Implement instance upgrade functionality
+
+export class InstanceUpgradeCommand {
+  async execute(): Promise<void> {
+    throw new Error('Not implemented');
+  }
+}