Project conventions detection: analyzes the indexed codebase to infer
coding patterns, naming conventions, error handling style, test organization,
and file structure. Useful for LLMs writing code that fits the project.
Session context tracking: records what the LLM has fetched this session
to enable deduplication hints, cache-hit short-circuits, and context inventory.
Tracks in-flight durable-ledger spawn_blocking writes so crate::server::serve::run
can drain them on shutdown instead of dropping economics events scheduled
just before SIGINT/SIGTERM (review finding P2-3).