Specter 2.01 enables camera autofocus overriding manual setup resulting in poor QR reading

**Describe the bug**
Specter overrides camera settings and reenables autofocus when the camera has already been manually set up with a focus for reading the QRs. This results in poor to unusable QR code scanning as the camera is unable to autofocus properly. I believe in prior versions Specter only turned on the camera without enabling autofocus.

**Expected behavior**
Expected behavior would be that Specter does not attempt to change the camera settings or enable autofocus. It only turns on.

**Desktop (please complete the following information):**
- Windows
- Specter Version 2.01

No file or test is named; start by locating the Python desktop camera initialization and autofocus handling for QR scanning, then compare it with the behavior described for prior versions. Done means Specter turns on a manually configured camera without changing its settings or re-enabling autofocus, while QR reading remains usable.

Written by the indexing model from the issue text.