fix(ext/console): make timer and counter state per-instance to fix OTEL console wrapping
When OTEL is enabled, `wrapConsole` calls both the OTEL Console and the
original Console methods sequentially. Since `timerMap` and `countMap` were
module-level singletons shared across all Console instances, the OTEL Console
would modify timer/counter state before the original Console ran, causing
spurious "Timer already exists" and "Timer does not exist" warnings.
Move `timerMap` and `countMap` to private instance fields so each Console
instance maintains independent state.
Fixes #28818
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>