feat: in-app Orchestrator (Phase 2) — multi-agent conductor

Brings the deterministic Han-flow conductor into BooCode: launch any read-only
flow from BooChat or BooCoder, watch each agent stream live in a Paseo-style
run pane, get an evidence-disciplined report — on local Qwen, persisted and
resumable. Read-only enforced hard via qwen --approval-mode plan (orchestrator
tasks fail closed if qwen is unavailable; never fall to write-capable native).

Backend (apps/coder): re-homed conductor defs, flow_runs/flow_steps schema,
flow-runner + dispatcher onTaskTerminal hook, restart-resume, runs routes
(launch/list/get/cancel), user-channel WS. Contracts: two flow_run_* frames.
Web: orchestrator pane kind + OrchestratorPane, Workflow button + slash flows
(BooChat/BooCoder parity), FlowLauncherDialog, "New Orchestrator" in the + and
split menus, runs history + export. Plan: openspec/changes/orchestrator.

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

apps/web/src/components/PaneHeaderActions.tsx

@@ -1,4 +1,4 @@
-import { Code, Columns2, History, MessageSquare, Plus, RotateCcw, Terminal, X } from 'lucide-react';
+import { Code, Columns2, History, MessageSquare, Plus, RotateCcw, Terminal, Workflow, X } from 'lucide-react';
 import {
   DropdownMenu,
   DropdownMenuContent,
@@ -16,6 +16,9 @@ interface Props {
   // (the second control) adds a new pane.
   onNewTab: (kind: 'chat' | 'terminal' | 'coder') => void;
   onSplitPane: (kind: 'chat' | 'terminal' | 'coder') => void;
+  // When provided, shows a "New Orchestrator" item that opens the flow launcher.
+  // Orchestrators are always split (run-bound; can't live as a tab in another pane).
+  onNewOrchestrator?: () => void;
   onReopenPane?: () => void;
   onShowHistory: () => void;
   onRemovePane?: () => void;
@@ -31,6 +34,7 @@ const BTN =
 export function PaneHeaderActions({
   onNewTab,
   onSplitPane,
+  onNewOrchestrator,
   onReopenPane,
   onShowHistory,
   onRemovePane,
@@ -62,6 +66,11 @@ export function PaneHeaderActions({
           <DropdownMenuItem onSelect={() => onNewTab('coder')}>
             <Code size={14} /> New BooCode
           </DropdownMenuItem>
+          {onNewOrchestrator && (
+            <DropdownMenuItem onSelect={onNewOrchestrator}>
+              <Workflow size={14} /> New Orchestrator
+            </DropdownMenuItem>
+          )}
         </DropdownMenuContent>
       </DropdownMenu>
 
@@ -87,6 +96,11 @@ export function PaneHeaderActions({
           <DropdownMenuItem onSelect={() => onSplitPane('coder')}>
             <Code size={14} /> New BooCode
           </DropdownMenuItem>
+          {onNewOrchestrator && (
+            <DropdownMenuItem onSelect={onNewOrchestrator}>
+              <Workflow size={14} /> New Orchestrator
+            </DropdownMenuItem>
+          )}
         </DropdownMenuContent>
       </DropdownMenu>