Resolve ByteArrayMemory volatile access support once

[andreas-karlsson]

This fixes the first part of #224, i.e. the catastrophic regression of ByteArrayMemory under JDK 25. It achieves this by calling isAccessModeSupported only once and reusing its result. On JDK 21 the call is cheap, but on JDK 25 where it returns false it's expensive.

Note: With this fix on JDK 25, ByteArrayMemory will fall back to the same lock path as ByteBufferMemory. Meaning roughly a 3x slowdown compared to JDK 21, so it still remains to provide a performant Memory impl. for JDK 25.

BenchmarkSievePrimes (4 threads, ops/s, higher is better; short runs: 1 fork, 3 iterations):

	JDK 21 before	JDK 21 after	JDK 25 before	JDK 25 after
compiled, ByteArrayMemory	71.8 ± 4.3	82.6 ± 18.0	0.32 ± 0.02	27.3 ± 10.0
compiled, ByteBufferMemory	23.2 ± 8.2	21.4 ± 1.2	23.7 ± 15.0	22.4 ± 11.7
interpreter, ByteArrayMemory	1.27 ± 0.50	1.25 ± 0.40	0.25 ± 0.10	0.78 ± 0.15
interpreter, ByteBufferMemory	0.97 ± 0.20	0.97 ± 0.49	0.86 ± 0.38	0.79 ± 0.38