N.I.N.A. Version 3.2 compatability fixes

[shurkanTwo]

• Target NINA 3.2 APIs: Bumped plugin metadata to require NINA ≥3.2.0.3001, rebuilt against the 3.2 SDK, and implemented ICamera.UpdateSubSampleArea so the Sony driver loads cleanly in 3.2.
• Restore ISO/Gain controls: Added change notifications after connection/disconnection and after gain writes, ensuring NINA’s UI repopulates ISO options immediately.
• Handle missing ISO lists: Cameras such as the A6600 don’t expose the ISO options table. Added a resilient helper that tolerates null descriptors, avoids crashes, and returns an empty list when necessary.
• Probe legacy ISO property: Some bodies still publish ISO options via the older 0xFFFE property. The driver now probes both 0xFFFE and 0xD21E, so the gain dropdown reappears on those models too.
• CI artifact improvements: Updated the GitHub Actions workflow to upload the release DLL directly from the build output.

Tested on NINA 3.2.0.9001 with a Sony a6400; the plugin loads, ISO controls populate, and exposures run normally.

[shurkanTwo]

I tested this version with the Sony a6400 and with the Sony a7 IV on two different windows 11 laptops.

[shurkanTwo]

@dougforpres Could you have a look at my changes. I am curious what you think :)
I also incorporated your review feedback from the other pr (#7)