Java 25 as the minimum required version

Context

At project inception, a minimum Java version was chosen. This decision affects which language and JDK features can be used, and which audience can adopt the library.

Decision

Require Java 25 as the minimum version.

Consequences

Positive:

• Access to Gatherer (Java 24+) to implement sequence/traverse with true short-circuit.
• Stable virtual threads (Java 21+) used in Try.withTimeout.
• Exhaustive pattern matching in switch over sealed interfaces.
• Record patterns, unnamed variables (_), and other post-17 features.

Negative / tradeoffs:

• Limits the audience to projects already migrated to Java 21+.
• Enterprise projects with slow upgrade cycles cannot adopt the library immediately.

Alternatives considered

• Java 21 (LTS): would have covered most features but excludes Gatherer.
• Java 17 (LTS): wider adoption, but lacks full sealed interfaces and advanced pattern matching.