Replace Jansi with JLine to resolve Java 21+ native access warnings

[david-waltermire]

Problem

When running the CLI on Java 21+, the following warnings are displayed:

WARNING: A restricted method in java.lang.System has been called
WARNING: java.lang.System::load has been called by org.fusesource.jansi.internal.JansiLoader in an unnamed module
WARNING: Use --enable-native-access=ALL-UNNAMED to avoid a warning for callers in this module
WARNING: Restricted methods will be blocked in a future release unless native access is enabled

This is caused by Jansi's use of native code loading via System.load(), which Java 21+ restricts as part of JEP 472: Prepare to Restrict the Use of JNI.

Current State

• Jansi version: 2.4.2 (org.fusesource.jansi:jansi)
• The warning is cosmetic but will become a blocking error in future Java releases
• The --enable-native-access=ALL-UNNAMED flag doesn't exist on older JREs, making it difficult to add conditionally

Proposed Solution

Migrate from Jansi to JLine:

1. Jansi has been merged into JLine - As of JLine 3.25, Jansi was merged into the JLine project
2. JLine 4.x removes Jansi entirely - Uses a JNI provider that handles native access more gracefully
3. JLine provides the FFM provider - For JDK 22+, JLine offers a Foreign Function & Memory (FFM) provider as an alternative to JNI

Migration Path

• Replace org.fusesource.jansi:jansi with org.jline:jline or specific JLine modules
• Update cli-processor to use JLine's terminal/console APIs
• The AnsiConsole and ANSI rendering functionality should have equivalent JLine APIs

References

• JLine GitHub
• Maven has the same issue - #11289
• JLine JPMS Support

Alternatives Considered

1. Custom launcher scripts - Add Java version detection to conditionally add --enable-native-access=ALL-UNNAMED
2. Document JAVA_OPTS workaround - Users manually set the flag
3. Accept the warning - Functional but not ideal for user experience

The JLine migration is preferred as it addresses the root cause and prepares for future Java releases.

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