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/coder/src/schema.sql

@@ -288,3 +288,72 @@ CREATE TRIGGER tasks_notify_new
   AFTER INSERT ON tasks
   FOR EACH ROW
   EXECUTE FUNCTION notify_tasks_new();
+
+-- v2.8.0: orchestrator flow_runs + flow_steps — DB-backed scheduler for multi-agent flows.
+-- project_id carries no FK (matches tasks.project_id convention, schema.sql:19).
+CREATE TABLE IF NOT EXISTS flow_runs (
+  id         UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+  project_id UUID NOT NULL,
+  flow_name  TEXT NOT NULL,
+  band       TEXT NOT NULL,
+  model      TEXT NOT NULL,
+  status     TEXT NOT NULL DEFAULT 'running',
+  input      JSONB NOT NULL,
+  report     TEXT,
+  error      TEXT,
+  created_at TIMESTAMPTZ NOT NULL DEFAULT clock_timestamp(),
+  updated_at TIMESTAMPTZ NOT NULL DEFAULT clock_timestamp(),
+  CONSTRAINT flow_runs_band_chk   CHECK (band   IN ('small', 'medium', 'large')),
+  CONSTRAINT flow_runs_status_chk CHECK (status IN ('running', 'completed', 'failed', 'cancelled')),
+  CONSTRAINT flow_runs_input_chk  CHECK (input ? 'question')
+);
+
+CREATE TABLE IF NOT EXISTS flow_steps (
+  id         UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+  run_id     UUID NOT NULL REFERENCES flow_runs(id) ON DELETE CASCADE,
+  step_id    TEXT NOT NULL,
+  kind       TEXT NOT NULL,
+  agent      TEXT,
+  status     TEXT NOT NULL DEFAULT 'pending',
+  task_id    UUID REFERENCES tasks(id) ON DELETE SET NULL,
+  chat_id    UUID REFERENCES chats(id) ON DELETE SET NULL,
+  input      TEXT,
+  output     TEXT,
+  error      TEXT,
+  created_at TIMESTAMPTZ NOT NULL DEFAULT clock_timestamp(),
+  updated_at TIMESTAMPTZ NOT NULL DEFAULT clock_timestamp(),
+  CONSTRAINT flow_steps_kind_chk   CHECK (kind   IN ('agent', 'code')),
+  CONSTRAINT flow_steps_status_chk CHECK (status IN ('pending', 'running', 'completed', 'failed', 'skipped', 'cancelled')),
+  UNIQUE (run_id, step_id)
+);
+
+-- Runs history query (GET /api/runs?project_id=).
+CREATE INDEX IF NOT EXISTS flow_runs_project_created_idx ON flow_runs(project_id, created_at DESC);
+
+-- Ready-wave derivation + resume scans (flow_steps WHERE run_id = ? AND status = ?).
+CREATE INDEX IF NOT EXISTS flow_steps_run_status_idx ON flow_steps(run_id, status);
+
+-- onTaskTerminal callback: look up the step owning a completed task.
+CREATE INDEX IF NOT EXISTS flow_steps_task_id_idx ON flow_steps(task_id);
+
+-- v2.8.0 (Phase 4): widen the status CHECKs to include 'cancelled' so the run
+-- pane's stop button has a terminal state to record (the plan Notes flagged this
+-- gap). Phase 2 applied these tables with the narrower set, so the inline CHECK
+-- edits above are no-ops on the existing DB (CREATE TABLE IF NOT EXISTS skips an
+-- existing table) — widen via the repo's DROP-IF-EXISTS → guarded-ADD discipline.
+-- Pure ADD of a new allowed value, so no row UPDATE is needed (no value renamed).
+ALTER TABLE flow_runs DROP CONSTRAINT IF EXISTS flow_runs_status_chk;
+DO $$ BEGIN
+  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'flow_runs_status_chk') THEN
+    ALTER TABLE flow_runs ADD CONSTRAINT flow_runs_status_chk
+      CHECK (status IN ('running', 'completed', 'failed', 'cancelled'));
+  END IF;
+END $$;
+
+ALTER TABLE flow_steps DROP CONSTRAINT IF EXISTS flow_steps_status_chk;
+DO $$ BEGIN
+  IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'flow_steps_status_chk') THEN
+    ALTER TABLE flow_steps ADD CONSTRAINT flow_steps_status_chk
+      CHECK (status IN ('pending', 'running', 'completed', 'failed', 'skipped', 'cancelled'));
+  END IF;
+END $$;