Migrate to Java 25

[Copilot]

Migrate from Java 11 to Java 25 using OpenRewrite's UpgradeToJava25 recipe, covering build tooling, CI, and source-level modernization.

Build & CI

• maven.compiler.release → 25, drop redundant maven.compiler.source
• maven-compiler-plugin 3.11.0 → 3.15.0
• maven-surefire-plugin / maven-failsafe-plugin 3.2.2 → 3.5.5 with --add-opens for reflective access
• CI workflow: JDK 11 → 25 (Temurin)

Source modernization

• Pattern matching for instanceof instead of cast-after-check
• Switch expressions replacing verbose switch statements
• Unnamed catch variables (_) where the exception is unused
• String.formatted() over String.format()

// Before
if (event instanceof Wizard) {
    Wizard w = (Wizard) event;
    return "Wizard registration: " + w.getFirstName();
}

// After
if (event instanceof Wizard w) {
    return "Wizard registration: " + w.getFirstName();
}

Note: Reverted the recipe's conversion of public static void main → instance void main — Dropwizard's Application subclass and the shade plugin's mainClass config require the traditional entry point.