nuthatch 2.7.2

A patch release for the operational work that landed after 2.7.1.

Drop-in. Replace the binary and restart. There is no config migration, data migration, or re-index.

Bounded runtime state and honest metrics

The runtime now bounds and evicts its DuckDB connections as mounts change, rather than keeping a
connection for every nest that has ever appeared. Departed nests also leave the process-wide metrics
registry. This keeps a long-lived multi-nest process from retaining dead state indefinitely.

Metrics no longer publish arbitrary cross-chain values as a global tip or lag. The process-wide
series are now scoped to values that can be represented honestly, while per-nest readiness and
progress remain the source of truth for a specific chain.

Analytics and control surfaces

Analytics invalidates cached DuckDB views when their nest inputs disappear. The SQL surface refuses
the mutation-shaped WITH forms DuckDB accepts, and the MCP path now invokes the advertised tool
rather than returning a description of one.

The wide-ABI admission path has a measured 2 GB ceiling, and the storage-path checks cover the clean
seal-direct route rather than merely an already-populated store.

Release engineering and documentation

CI has stronger required-context and behavioural checks. The operator, benchmark, launch, and
mapping documentation now records the measurements and limitations it relies on, including where a
normal query-time view is not incremental materialisation.

Not in this release

RFC-0041 authored incremental entities are still under implementation. The compiler gate and
authoring validation are deliberately not presented here as a shipped indexing-time feature. That
work belongs to 3.0.0 once its lifecycle and serving paths exist.