agents: discussion mode — devs talk in threads; building starts only on explicit signal

Mentioning a dev agent no longer spawns a branch + PR machinery. It is a
CONVERSATION by default: the dev reads what it needs and replies in-thread.

- route.sh: workmode=build|discuss for mode=pr agents. Build ONLY on the
  explicit signals: PR-thread comments (resume), the pm delegation template
  ("please proceed with issue …" — a human can write it too), or the qa bounce
  ("please address my review …"). Everything else = discuss: no branch prep,
  no "🔨 Building" notice.
- run-agent.sh: discussion ACTION for devs (read-only consult, no edits/
  commits/markers). @pm gains 'ASK: @<dev> <question>' to consult devs before
  planning — gather feasibility/effort input, then DELEGATE when enough is
  known. One ASK per reply; never ASK+DELEGATE together.
- publish.sh: pm ASK handler posts the question as a discussion trigger; dev
  discuss path posts the reply (+run report) and skips ALL git/PR machinery
  (stray edits discarded). ASK marker stripped from visible replies.
- agent.yml: WORKMODE threaded to Run-agent + Publish. README documents it.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.gitea/workflows/scripts/publish.sh

@@ -73,6 +73,7 @@ reply=$(awk '
   /^[[:space:]]*BEGIN_SUBTASKS/{s=1}
   /^[[:space:]]*BEGIN_PR_DESCRIPTION/{p=1}
   /^[[:space:]]*DELEGATE:[[:space:]]*@/{next}
+  /^[[:space:]]*ASK:[[:space:]]*@/{next}
   /^[[:space:]]*CLOSE_ISSUE[[:space:]]*$/{next}
   /^[[:space:]]*MERGE_PR[[:space:]]*$/{next}
   /^[[:space:]]*RETRO[[:space:]]*$/{next}
@@ -246,6 +247,18 @@ if [ "$MODE" != "pr" ]; then
     exit 0
   fi
 
+  # --- @pm ASK: consult a dev in the thread WITHOUT starting a build ---
+  # 'ASK: @<dev> <question>' fires the dev in DISCUSSION mode (route.sh: the trigger below does not
+  # match any build phrase, so the dev replies in-thread — no branch, no PR). @pm gathers input this
+  # way, then DELEGATEs when enough is known.
+  ask_line=$(grep -oiE '^[[:space:]]*ASK:[[:space:]]*@(junior|senior|lead|intern)[[:space:]]+.*$' /tmp/agent_out.md 2>/dev/null | head -1)
+  if [ "$NAME" = "pm" ] && [ -n "$ask_line" ]; then
+    ask_dev=$(printf '%s' "$ask_line" | grep -oiE '@(junior|senior|lead|intern)' | head -1 | tr -d '@' | tr '[:upper:]' '[:lower:]')
+    ask_q=$(printf '%s' "$ask_line" | sed -E 's/^[[:space:]]*ASK:[[:space:]]*@[A-Za-z]+[[:space:]]+//')
+    trig "$ISSN" "@$ask_dev $ask_q — this is a discussion: reply in this thread with your assessment; do not start any work."
+    exit 0
+  fi
+
   # --- @pm delegation: hand the build to a dev, or hand the finished PR to @qa for review ---
   # Only an explicit 'DELEGATE: @<agent>' line acts (never a prose mention). Fires via the PAT (TTOK)
   # so a new run starts; the built-in token cannot. Everything posts on the ISSUE — @pm never touches
@@ -269,6 +282,15 @@ if [ "$MODE" != "pr" ]; then
   exit 0
 fi
 
+# --- dev DISCUSSION mode: consulted for expertise, no build (route.sh workmode=discuss) ---
+# The reply is a comment on the thread — discard any stray file edits, skip ALL git/PR machinery.
+if [ "${WORKMODE:-build}" = "discuss" ]; then
+  git checkout -- . 2>/dev/null || true
+  git clean -fd  2>/dev/null || true
+  post "$(printf '%s%s' "$reply" "$activity")"
+  exit 0
+fi
+
 # Scrub the runtime scripts checkout (.agents-workflow) from the tree so it never lands in a
 # commit/PR and never confuses the git ops below (issue #33). The scripts we run live outside the
 # workspace ($SCRIPTS -> runner.temp), so removing this in-tree copy is always safe. Handle every