feat: r0 coordinator tooling for orchestrator protocol

Implements the manual coordinator workflow for multi-session agent
orchestration. Agents stop after one milestone (confirmed limitation);
these tools let the human coordinator check status, generate continuation
prompts, and chain sessions together.

New:
- tools/orchestrator/ — 5 scripts + shared library (_lib.sh)
  - mission-init.sh: initialize mission with milestones and state files
  - mission-status.sh: dashboard showing milestones, tasks, sessions
  - session-status.sh: check if agent is running/stale/dead
  - continue-prompt.sh: generate paste-ready continuation prompt
  - session-resume.sh: crash recovery with dirty state detection
- guides/ORCHESTRATOR-PROTOCOL.md: agent-facing mission lifecycle guide
- templates/docs/: mission manifest, scratchpad, continuation templates
- templates/repo/.mosaic/orchestrator/mission.json: state file template

Modified:
- bin/mosaic: add 'coord' subcommand + resume advisory on launch
- AGENTS.md: conditional loading for protocol guide + rule 37
- bin/mosaic-doctor: checks for new coordinator files
- session hooks: mission detection on start, cleanup on end

Usage: mosaic coord init|mission|status|continue|resume

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

templates/repo/scripts/agent/session-end.sh

@@ -8,6 +8,34 @@ source "$SCRIPT_DIR/common.sh"
 ensure_repo_root
 load_repo_hooks
 
+# ─── Mission session cleanup (ORCHESTRATOR-PROTOCOL) ────────────────────────
+ORCH_DIR=".mosaic/orchestrator"
+MISSION_JSON="$ORCH_DIR/mission.json"
+SESSION_LOCK="$ORCH_DIR/session.lock"
+COORD_LIB="$HOME/.config/mosaic/tools/orchestrator/_lib.sh"
+
+if [[ -f "$SESSION_LOCK" ]] && [[ -f "$COORD_LIB" ]] && command -v jq &>/dev/null; then
+  # shellcheck source=/dev/null
+  source "$COORD_LIB"
+
+  sess_id="$(jq -r '.session_id // ""' "$SESSION_LOCK")"
+  if [[ -n "$sess_id" && -f "$MISSION_JSON" ]]; then
+    # Update mission.json: mark session ended
+    updated="$(jq \
+      --arg sid "$sess_id" \
+      --arg ts "$(iso_now)" \
+      --arg reason "completed" \
+      '(.sessions[] | select(.session_id == $sid)) |= . + {
+        ended_at: $ts,
+        ended_reason: $reason
+      }' "$MISSION_JSON")"
+    echo "$updated" > "$MISSION_JSON.tmp" && mv "$MISSION_JSON.tmp" "$MISSION_JSON"
+    echo "[agent-framework] Session $sess_id recorded in mission state"
+  fi
+
+  session_lock_clear "."
+fi
+
 if declare -F mosaic_hook_session_end >/dev/null 2>&1; then
   run_step "Run repo end hook" mosaic_hook_session_end
 else

templates/repo/scripts/agent/session-start.sh

@@ -16,6 +16,72 @@ if git rev-parse --is-inside-work-tree >/dev/null 2>&1 && has_remote; then
   fi
 fi
 
+# ─── Mission state detection (ORCHESTRATOR-PROTOCOL) ────────────────────────
+ORCH_DIR=".mosaic/orchestrator"
+MISSION_JSON="$ORCH_DIR/mission.json"
+COORD_LIB="$HOME/.config/mosaic/tools/orchestrator/_lib.sh"
+
+if [[ -f "$MISSION_JSON" ]] && command -v jq &>/dev/null; then
+  mission_status="$(jq -r '.status // "inactive"' "$MISSION_JSON")"
+
+  if [[ "$mission_status" == "active" || "$mission_status" == "paused" ]]; then
+    mission_name="$(jq -r '.name // "unnamed"' "$MISSION_JSON")"
+    echo ""
+    echo "========================================="
+    echo "ACTIVE MISSION DETECTED"
+    echo "========================================="
+    echo "  Mission: $mission_name"
+
+    # Extract key fields from manifest if present
+    manifest="docs/MISSION-MANIFEST.md"
+    if [[ -f "$manifest" ]]; then
+      phase="$(grep -m1 '^\*\*Phase:\*\*' "$manifest" 2>/dev/null | sed 's/.*\*\*Phase:\*\* //' || true)"
+      milestone="$(grep -m1 '^\*\*Current Milestone:\*\*' "$manifest" 2>/dev/null | sed 's/.*\*\*Current Milestone:\*\* //' || true)"
+      progress="$(grep -m1 '^\*\*Progress:\*\*' "$manifest" 2>/dev/null | sed 's/.*\*\*Progress:\*\* //' || true)"
+      [[ -n "$phase" ]] && echo "  Phase: $phase"
+      [[ -n "$milestone" ]] && echo "  Milestone: $milestone"
+      [[ -n "$progress" ]] && echo "  Progress: $progress"
+    fi
+
+    # Task counts
+    if [[ -f "docs/TASKS.md" ]]; then
+      total="$(grep -c '^|' "docs/TASKS.md" 2>/dev/null || echo 0)"
+      done_count="$(grep -ci '| done \|| completed ' "docs/TASKS.md" 2>/dev/null || echo 0)"
+      echo "  Tasks: ~$done_count done of ~$((total - 2)) total"
+    fi
+
+    # Scratchpad
+    if [[ -d "docs/scratchpads" ]]; then
+      latest_sp="$(ls -t docs/scratchpads/*.md 2>/dev/null | head -1 || true)"
+      [[ -n "$latest_sp" ]] && echo "  Scratchpad: $latest_sp"
+    fi
+
+    echo ""
+    echo "  Resume: Read manifest + scratchpad before taking action."
+    echo "  Protocol: ~/.config/mosaic/guides/ORCHESTRATOR-PROTOCOL.md"
+    echo "========================================="
+    echo ""
+
+    # Register session if coordinator lib is available
+    if [[ -f "$COORD_LIB" ]]; then
+      # shellcheck source=/dev/null
+      source "$COORD_LIB"
+      sess_id="$(next_session_id ".")"
+      runtime="${MOSAIC_RUNTIME:-unknown}"
+      session_lock_write "." "$sess_id" "$runtime" "$$"
+
+      # Append session to mission.json
+      updated="$(jq \
+        --arg sid "$sess_id" \
+        --arg rt "$runtime" \
+        --arg ts "$(iso_now)" \
+        '.sessions += [{"session_id":$sid,"runtime":$rt,"started_at":$ts,"ended_at":"","ended_reason":"","milestone_at_end":"","tasks_completed":[],"last_task_id":""}]' \
+        "$MISSION_JSON")"
+      echo "$updated" > "$MISSION_JSON.tmp" && mv "$MISSION_JSON.tmp" "$MISSION_JSON"
+    fi
+  fi
+fi
+
 if declare -F mosaic_hook_session_start >/dev/null 2>&1; then
   run_step "Run repo start hook" mosaic_hook_session_start
 else