Fix the remaining SonarCloud issues in Controller and AutosaveController

[mfl28]

Follow-up to #228 and #229: the SonarCloud issues left in Controller, and two that came in with AutosaveController. No behavior changes.

Controller

• Four methods that only one Operations class uses moved into that class (S3398):
  • startImageMetaDataLoadingService, updateViewImageFiles and clearViewAndModel into ImageFolderOperations;
  • clearModelAndViewAnnotationData into AnnotationIoOperations.
• An unused catch variable is unnamed (S7467).

AutosaveController

• Blocker S1845: the field delay and the constant DELAY differed only in case. They're now saveTimer and SAVE_DELAY.
• Major S107: the constructor had 8 parameters. The timer is now created through Operations.createTimer, next to the other JavaFX-related operations, so it has 7. The app's Controller returns AutosaveController.createSaveTimer (a PauseTransition), and the unit tests return their fake timer from the mocked Operations.

The full suite (306 tests) passes locally.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
98.4% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

❌ Patch coverage is 98.38710% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 90.24%. Comparing base (fc23983) to head (c62b09d).
⚠️ Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
...mfl28/boundingboxeditor/controller/Controller.java	98.11%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff            @@
##             master     #230   +/-   ##
=========================================
  Coverage     90.24%   90.24%           
+ Complexity     2389     2384    -5     
=========================================
  Files           140      140           
  Lines          8963     8964    +1     
  Branches        860      860           
=========================================
+ Hits           8089     8090    +1     
  Misses          455      455           
  Partials        419      419           

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