Two more helpers needed for end-to-end multi-user attribution:
- IsSystemSenderID filters synthetic trigger sources (cron, heartbeat,
async:* tool callbacks, system channel) so internal events do not
surface as distinct human users in the conversation. Without this,
cron-triggered messages would carry attribution like cron, producing
a confusing [cron] [System: cron] ... double prefix on adapters that
fall back to in-content rendering.
- ApplyUserNamePrefix renders msg.Name as a [name] prefix on user
content for adapters whose APIs do not support a per-message author
identity (Anthropic, Bedrock, OpenAI Responses). The persisted
message is never mutated; only the wire payload carries the prefix.
Tool result messages and non-user roles pass through unchanged.
These helpers are pure and independently testable; they will be wired
into the agent and provider adapters in subsequent commits.
Refs #2702.
7c7d7146ef