fix(observability): resolve A2A and plugin post-invoke silent-success traps#4238

bogdanmariusc10 wants to merge 4 commits intomainIBM/mcp-context-forge:mainfrom

4211-bug-silent-success-metric-traps-in-a2a-200-ok-path-and-plugin-tool_post_invoke-mutationIBM/mcp-context-forge:4211-bug-silent-success-metric-traps-in-a2a-200-ok-path-and-plugin-tool_post_invoke-mutationCopy head branch name to clipboard