Expose Maven logging output capabilities in Maven 4.1

[wilx]

Plugins currently have to inspect logging internals to learn where Maven writes and which charset it uses. Add an injectable OutputCapabilities service plus an immutable maven.logging.outputCapabilities map in execution-request data for plugins compiled against older Maven APIs.

Capture the actual logging route, report uncertain detection as UNKNOWN, and preserve resident-invocation cleanup without changing output routing or encoding.

Validation: reactor verification (excluding existing IDE .iml files), focused Core ITs, and Linux runtime checks passed. macOS and Windows remain untested.

• I license this contribution under the Apache License 2.0.

[gnodet]

Thanks for this contribution — the use case is real and the API design (OutputCapabilities as an injectable service with a fallback Map<String, String> in request data for older-API plugins) is clean.

A few thoughts before this can move forward:

Milestone / branch targeting

This PR targets master (4.1.0), which is the right vehicle. However, the integration points it touches — LookupInvoker, LookupContext, and PlexusContainerCapsule.updateLogging() — are actively being reshaped by the logging feature chain currently under review (#12694, #13180, and related PRs). This PR will need to be rebased on top of feature/console-modes (#13180) before it can be cleanly reviewed, as the context initialization path is changing there.

Interaction with --console=machine

When --console=machine is active (#13180), Maven writes JSON lines to stdout rather than using the terminal for human-readable output. In that case, Destination should be deterministically REDIRECTED (or a new MACHINE value) derived directly from the console mode flag, not from JLine terminal introspection. Right now TerminalOutputCapabilities.destination() will likely give the right answer incidentally (dumb terminal → REDIRECTED), but it's fragile — if the stdout routing ever changes in machine mode, the detection would silently regress. Once rebased on feature/console-modes, the MavenInvoker.determineConsoleMode() result should feed directly into the outputCapabilities supplier in LookupContext.

Backports (#13209, #13210)

I'd recommend keeping the 3.10.x and 4.0.x backports as drafts for now. This is new API surface, not a bug fix, and adding a new injectable service to maintenance branches is invasive. If dependency:tree or other tools have a concrete regression to fix, that's a different conversation — but the general feature belongs in 4.1.0.