Adds DigestAccumulator tracking ACTIVE NOW and SINCE LAST DIGEST
state per toggle. Replaces StubDigestQueue in build_pipeline; the
stub class is kept for Phase 2.1 backward-compat tests.
- enqueue(): adds new events, updates in place by id, detects
resolutions (expires past, or title contains cleared/reopened/
ended/resolved/back online/recovered/lifted)
- tick(now): rolls expired actives into since_last
- render_digest(now): produces a Digest with mesh_compact (<=200
chars) and full multi-line forms; clears since_last after
- Toggle ordering and labels match the v0.3 design
- Phase 2.3b will add real scheduling on top of this
Adds inline pipeline stages between the bus and the severity router:
- Inhibitor: suppresses lower-or-equal severity events when a key
in event.inhibit_keys is already active. TTL configurable, default
30 minutes.
- Grouper: coalesces events sharing group_key within a time window
(default 60s). Most recent event wins. tick() and flush_all()
drive emission; no background timers in Phase 2.2.
- build_pipeline now wires: bus -> inhibitor -> grouper -> severity_router
Phase 2.1 dispatcher tests continue to pass unchanged.
