Research confirms StartOS 0.4 supports per-package SMTP credentials fully
independent of the server's system account: the "custom" branch of the
manage-smtp action (gitea-startos and vaultwarden-startos both) never calls
getSystemSmtp and works on a box with no system SMTP. Record this as the likely
fit (a digest-only mailbox), built on sdk.inputSpecConstants.smtpInputSpec, plus
the SDK version caveat (our ^0.4.0-beta.66 pin vs the references' 1.x).
Fold the research into the daily-digest item: outbound mail uses the StartOS
0.4 system SMTP account via sdk.getSystemSmtp(effects).const(), delivered to the
Python process as env vars from the daemon exec block (gitea-startos pattern,
mirroring the existing setAnthropicApiKey action). Notes the action+storeJson
config model that replaced the 0.3 manifest Config/Properties spec.
Records the requested per-user daily digest (who emailed which investors +
email substance) as a post-Phase-1 backlog item. Notes the three build-shaping
constraints: the new outbound-SMTP dependency (no current send path), the
Spark-only / never-Claude analysis rule for the un-anonymized substance, and
the internal-digest exemption from the "agents draft, humans send" guardrail.
Keysat