Java 17 Features

Migrate in incremental hops (8 to 11 to 17), fixing removed modules and strong encapsulation at each LTS, then update libraries and adopt new language features.

Five breaking changes from Java 8 to 17: strong encapsulation blocks reflection into JDK internals, removed modules need Jakarta dependencies, CMS GC and other JVM flags are gone, G1 is the default GC, and frameworks require version bumps. module-info.java is not required.

Java 17 is an LTS release that finalizes records, sealed classes, pattern matching instanceof, switch expressions, and text blocks as the modern enterprise baseline.