Closes the biggest gap between the running execution engine and
ECOSYSTEM-SPEC.md §4.3: confirmations were entirely unmodeled, so any
capability could execute unconfirmed regardless of requires_confirmation.
- New confirmations table + Confirmation domain type; POST
/api/v1/confirmations mints a TTL-bound (120s) confirmation binding
capability id+version, target entity, and a sorted-key args hash.
- Execute() now requires a valid pending confirmation when the
capability demands one: rejects missing, expired, consumed, or
args/version-mismatched confirmations; consumes on success.
- Capabilities gain enabled (destructive risk defaults to disabled,
matching "must be turned on explicitly") and timeout_seconds.
- One in-flight execution per (capability_id, target_entity_id); a
second concurrent attempt is rejected (surfaced as 409 over HTTP).
- Wall-clock timeout per capability now wraps the provider call; on
timeout the outcome is "unknown" (new ExecutionStatus), never
"failed", and the run is never auto-retried.
- 9 new engine tests cover each guard from the spec's Phase 6 gate.
Vikunja #274.
kami