Compaction and forked-agent queries can now skip inline cache markers

What

• The internal forked-agent query runner gained a skipMessageCacheMarkers option, alongside the existing skipTranscript/skipCacheWrite options, threaded into the underlying streaming query call.
• The core compaction/summarization call now accepts the same skipMessageCacheMarkers option (defaulting to false), passed through to the underlying compaction function.
• When enabled, compaction requests omit cache markers on messages under certain conditions, gated by the tengu_groovy_eclipse feature flag.

Why Cache markers help Claude Code reuse previously-computed context, but they're not always needed; this gives compaction and forked-agent requests a way to skip them when appropriate.