Release v3.0.0

Added

• DayKey, the daily counterpart to WeekKey and MonthKey.
• AgentUsageBucketKey, the day/provider/agent/purpose/model bucket a daily usage row accumulates under.
• AgentSessionUsageRecorded now carries a precomputed DayKey and DailyBucketKey, for the reason its own remarks already give for WeekKey/MonthKey: Chronicle's model-bound key resolution keys a projection on a single event property, so a composite bucket has nowhere else to come from.
• UsagePeriod now carries the resolved Day and DailyBucket alongside Week and Month.

Breaking

• AgentSessionUsageRecorded and UsagePeriod gained required positional parameters. Code constructing either directly must supply them; RecordAgentSessionUsage.Provide resolves them for the normal path.
• AgentUsageByDay's shape and the signature of AgentUsageByDay.LastYear changed as described above.

Changed

• AgentUsageByDay is now a real accumulating projection instead of a [Passive] read model. It previously recomputed a year of buckets with an in-memory GroupBy over every session recorded in the trailing 371-day window on every read, a cost that grows without bound with the number of sessions to answer a question whose answer only changes by one session at a time. AgentUsageByWeek and AgentUsageByMonth were already real projections; the daily model is now keyed and accumulated the same way.
• AgentUsageByDay.LastYear now reads the accumulated buckets from its own collection and takes an IMongoCollection<AgentUsageByDay> and a TimeProvider, replacing the previous IRecordedAgentSessions parameter.
• AgentUsageByDay now exposes the day as a DayKey and carries BucketKey, CachedTokens and DurationMs; total session time remains available as the Duration property.