XY-1061: [ELF AMK P1] Add agent-facing recall API and explainable Recall Debug trace

[yvette-carlisle]

Summary

• add public agent-facing recall debug panel access with deterministic elf.recall_trace/v1 readback
• expose selected, dropped, stale, blocked, and not-requested recall context across memory, docs, knowledge, graph, and Dreaming layers
• gate public trace-memory hydration to same-agent/read-profile trace context while preserving admin operator readback

Validation

• cargo make fmt
• cargo make lint-fix
• cargo make checks
• focused cargo test -p elf-service recall_debug --all-features

Review

• independent Decodex repair review checkpoint is clean for HEAD dabab49e7d9c8c032ad07d392837a51c81ad2f56