QA REJECT-P1 remediation (seq 29). start()/done()/is_done()/get_output()
were asymmetric: start() passed the mapped role but done()/is_done()/
get_output() passed '' via the default, addressing a different unique key
(run_id, stage, agent_role, item_key). On every normal run this orphaned
the start() row in 'running'; on resume is_done() always returned false
→ duplicate-post vector.
Fix: add resolve_role(stage, agent_role) private static seam in
Run_Stage_State. When the caller passes '' the role is derived from
Stage_Display_Map::default_agent_role(stage) before any DB operation.
Non-empty roles (Phase-2 fan-out) pass through unchanged. All four
write/lookup methods (start, done, fail, get) call resolve_role.
is_done() and get_output() go through get() so they benefit too.
Mid-run-upgrade compat (v0.18.1 → v0.18.2): get() falls back to a
legacy role='' row on miss so a run started under v0.18.1 (all rows
have agent_role='') can still resume under v0.18.2. One extra indexed
query, only on miss, only for known stages.
Tests: two new RunStageStateTest cases —
test_role_tagged_start_and_done_are_symmetric: start+done with
'editor', assert is_done('editor')=true and is_done('')=false.
test_legacy_empty_role_row_is_found_on_fallback: resolve to 'editor',
primary miss, legacy role='' hit → is_done=true.
ARCHITECTURE.md §22: agent_role column and #22 Phase 1 description
updated — no longer 'Phase-2 only / '' default'; now documents Phase 1
population from Stage_Display_Map.
Agent-Session: prab-v0182-maintenance-20260612
3af65bbe39