Pipe structured BuilderProblems directly into DiagnosticCollector instead of re-logging as text

[gnodet]

Context

PR #12572 (Build Report Foundation) introduced a warning collection pipeline that intercepts SLF4J WARN-level log calls via BuildReportCollector.captureLogEvent() and auto-creates BuilderProblem objects with synthetic keys (auto:xxx).

However, Maven already creates structured BuilderProblem objects during model/settings/toolchains validation (with key, suggestion, documentationUrl, source:line:column) and plugin validation (deprecated mojos, Maven 2 dependencies, etc.). These are currently re-logged as plain text, losing all structured metadata.

Problem

When the SLF4J hook intercepts the re-logged text, it creates a new synthetic BuilderProblem with:

• An auto-generated key (auto:logger-name:hash) instead of the original meaningful key
• No suggestion
• No documentationUrl
• No source location

The original structured BuilderProblem data is discarded.

Implementation Status

✅ Done — Plugin validation (PR #12647)

PR #12647 implements structured BuilderProblem piping for all plugin validation pathways:

Pathway	Component	Status
1 — Model validation	DefaultModelProblemCollector	✅ Verified existing
2 — Plugin parameter validation	AbstractMavenPluginParametersValidator (3 validators)	✅ Implemented
3 — Plugin dependency validation	AbstractMavenPluginDependenciesValidator (4 validators)	✅ Implemented
4 — Contextualizable check	DefaultMavenPluginManager	✅ Implemented
5 — PluginValidationManager API	Migrated from String → BuilderProblem	✅ Implemented

Additionally, PluginValidationManager was migrated to accept BuilderProblem natively, with deprecated String-based default methods for backward compatibility.

🔲 Remaining — Settings and toolchains validation

In LookupInvoker and MavenInvoker, settings/toolchains BuilderProblem objects are still re-logged as text before being captured. Same pattern as above — pipe the original BuilderProblem directly instead of only logging the message text.

Validators affected

Validator	Status
DefaultModelValidator (~35 sites)	✅ Already structured (Pathway 1)
DeprecatedPluginValidator	✅ PR #12647
Maven2DependenciesValidator	✅ PR #12647
Maven3CompatDependenciesValidator	✅ PR #12647
MavenScopeDependenciesValidator	✅ PR #12647
MavenMixedDependenciesValidator	✅ PR #12647
ReadOnlyPluginParametersValidator	✅ PR #12647
DeprecatedCoreExpressionValidator	✅ PR #12647
DefaultSettingsValidator (~15 sites)	🔲 Remaining
DefaultToolchainsBuilder	🔲 Remaining
Profile activators (File, JDK)	🔲 Remaining

Expected Outcome

mvnlog --diagnostics displays full structured information:

Problems: 2 warnings

  [WARN]  'prerequisites' is deprecated   pom.xml
          key: deprecated-prerequisites
          suggestion: Use the maven-enforcer-plugin instead
          docs: https://maven.apache.org/pom.html#prerequisites

  [WARN]  Plugin uses deprecated Maven 2 API   maven-shade-plugin:3.5.0
          key: plugin-maven2-dependency
          suggestion: Update to a version that uses Maven 4 API

Depends on

• Build report, console modes, and warning control #12572 (Build Report Foundation)