refactor: rename factory/ → supervisor/, factory-poll → supervisor-poll

The supervisor agent was confusingly named "factory" (same as the
project). Rename directory, script, log, lock, status, and escalation
files. Update all references across scripts and docs.

FACTORY_ROOT env var unchanged (refers to project root, not agent).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

dev/dev-agent.sh

@@ -1106,9 +1106,9 @@ while [ "$REVIEW_ROUND" -lt "$MAX_REVIEW_ROUNDS" ]; do
     CI_FIX_COUNT=$(( ${CI_FIX_COUNT:-0} + 1 ))
     if [ "$CI_FIX_COUNT" -gt 2 ]; then
       log "CI failure not recoverable after ${CI_FIX_COUNT} fix attempts"
-      # Escalate to supervisor — write marker for factory-poll.sh to pick up
+      # Escalate to supervisor — write marker for supervisor-poll.sh to pick up
       echo "{\"issue\":${ISSUE},\"pr\":${PR_NUMBER},\"reason\":\"ci_exhausted\",\"step\":\"${FAILED_STEP:-unknown}\",\"attempts\":${CI_FIX_COUNT},\"ts\":\"$(date -u +%Y-%m-%dT%H:%M:%SZ)\"}" \
-        >> "${FACTORY_ROOT}/factory/escalations.jsonl"
+        >> "${FACTORY_ROOT}/supervisor/escalations.jsonl"
       log "escalated to supervisor via escalations.jsonl"
       break
     fi

dev/dev-poll.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env bash
-# dev-poll.sh — Pull-based factory: find the next ready issue and start dev-agent
+# dev-poll.sh — Pull-based scheduler: find the next ready issue and start dev-agent
 #
 # Pull system: issues labeled "backlog" are candidates. An issue is READY when
 # ALL its dependency issues are closed (and their PRs merged).
@@ -104,7 +104,7 @@ dep_is_merged() {
     return 1
   fi
 
-  # Issue closed = dep satisfied. The factory only closes issues after
+  # Issue closed = dep satisfied. The scheduler only closes issues after
   # merging, so closed state is trustworthy. No need to hunt for the
   # specific PR — that was over-engineering that caused false negatives.
   return 0