Fix: Add JavaFX requirement check on startup

[mgaffigan]

Adds a startup check to verify the environment is acceptable to the app. Can't check for java version since we're targeting bytecode 61, but does check Java FX.

Here's the new startup error.

Tested using Azul Zulu JRE 17 FX and SE

Closes #277

[github-actions]

Test Results

  110 files  ±0    212 suites  ±0   7m 0s ⏱️ + 1m 8s
  650 tests ±0    650 ✅ ±0  0 💤 ±0  0 ❌ ±0 
1 300 runs  ±0  1 300 ✅ ±0  0 💤 ±0  0 ❌ ±0 

Results for commit df599f8. ± Comparison against base commit bfe3348.

[NicoPiel]

Hmm.. this would prompt some people to go "It says Java 17 required and Java 17 installed.. what am I doing wrong?"

[mgaffigan]

@NicoPiel

Hmm.. this would prompt some people to go "It says Java 17 required and Java 17 installed.. what am I doing wrong?"

At some point, they do have to understand the difference between SE and FX, but I'm open to other phrasing.

I also assume the message will be used for version issues in the future.

[edthri]

As well as 'Detected Java runtime' could it have a second line addressing the other key factor? e..g. 'JFX..." Displaying JFX version could be confusing so maybe display a status such as 'Present' or 'Not Found'?