feat(kanban): durable multi-profile collaboration board (#17805)

Salvage of PR #16100 onto current main (after emozilla's #17514 fix
that unblocks plugin Pydantic body validation). History preserved on
the standing `feat/kanban-standing` branch; this squashes the 22
iterative commits into one clean landing.

What this lands:
- SQLite kernel (hermes_cli/kanban_db.py) — durable task board with
  tasks, task_links, task_runs, task_comments, task_events,
  kanban_notify_subs tables. WAL mode, atomic claim via CAS,
  tenant-namespaced, skills JSON array per task, max-runtime timeouts,
  worker heartbeats, idempotency keys, circuit breaker on repeated
  spawn failures, crash detection via /proc/<pid>/status, run history
  preserved across attempts.
- Dispatcher — runs inside the gateway by default
  (`kanban.dispatch_in_gateway: true`). Ticks every 60s, reclaims
  stale claims, promotes ready tasks, spawns `hermes -p <assignee>
  chat -q "work kanban task <id>"` with HERMES_KANBAN_TASK +
  HERMES_KANBAN_WORKSPACE env. Auto-loads `--skills kanban-worker`
  plus any per-task skills. Health telemetry warns on stuck ready
  queue.
- Structured tool surface (tools/kanban_tools.py) — 7 tools
  (kanban_show, kanban_complete, kanban_block, kanban_heartbeat,
  kanban_comment, kanban_create, kanban_link). Gated on
  HERMES_KANBAN_TASK via check_fn so zero schema footprint in normal
  sessions.
- System-prompt guidance (agent/prompt_builder.py KANBAN_GUIDANCE)
  injected only when kanban tools are active.
- Dashboard plugin (plugins/kanban/dashboard/) — Linear-style board
  UI: triage/todo/ready/running/blocked/done columns, drag-drop,
  inline create, task drawer with markdown, comments, run history,
  dependency editor, bulk ops, lanes-by-profile grouping, WS-driven
  live refresh. Matches active dashboard theme via CSS variables.
- CLI — `hermes kanban init|create|list|show|assign|link|unlink|
  claim|comment|complete|block|unblock|archive|tail|dispatch|context|
  init|gc|watch|stats|notify|log|heartbeat|runs|assignees` +
  `/kanban` slash in-session.
- Worker + orchestrator skills (skills/devops/kanban-worker +
  kanban-orchestrator) — pattern library for good summary/metadata
  shapes, retry diagnostics, block-reason examples, fan-out patterns.
- Per-task force-loaded skills — `--skill <name>` (repeatable),
  stored as JSON, threaded through to dispatcher argv as one
  `--skills X` pair per skill alongside the built-in kanban-worker.
  Dashboard + CLI + tool parity.
- Deprecation of standalone `hermes kanban daemon` — stub exits 2
  with migration guidance; `--force` escape hatch for headless hosts.
- Docs (website/docs/user-guide/features/kanban.md + kanban-tutorial.md)
  with 11 dashboard screenshots walking through four user stories
  (Solo Dev, Fleet Farming, Role Pipeline, Circuit Breaker).
- Tests (251 passing): kernel schema + migration + CAS atomicity,
  dispatcher logic, circuit breaker, crash detection, max-runtime
  timeouts, claim lifecycle, tenant isolation, idempotency keys, per-
  task skills round-trip + validation + dispatcher argv, tool surface
  (7 tools × round-trip + error paths), dashboard REST (CRUD + bulk
  + links + warnings), gateway-embedded dispatcher (config gate, env
  override, graceful shutdown), CLI deprecation stub, migration from
  legacy schemas.

Gateway integration:
- GatewayRunner._kanban_dispatcher_watcher — new asyncio background
  task, symmetric with _kanban_notifier_watcher. Runs dispatch_once
  via asyncio.to_thread so SQLite WAL never blocks the loop. Sleeps
  in 1s slices for snappy shutdown. Respects HERMES_KANBAN_DISPATCH_IN_GATEWAY=0
  env override for debugging.
- Config: new `kanban` section in DEFAULT_CONFIG with
  `dispatch_in_gateway: true` (default) + `dispatch_interval_seconds: 60`.
  Additive — no \_config_version bump needed.

Forward-compat:
- workflow_template_id / current_step_key columns on tasks (v1 writes
  NULL; v2 will use them for routing).
- task_runs holds claim machinery (claim_lock, claim_expires,
  worker_pid, last_heartbeat_at) so multi-attempt history is first-
  class from day one.

Closes #16102.

Co-authored-by: emozilla <emozilla@nousresearch.com>

agent/prompt_builder.py

@@ -182,6 +182,64 @@ SKILLS_GUIDANCE = (
     "Skills that aren't maintained become liabilities."
 )
 
+KANBAN_GUIDANCE = (
+    "# You are a Kanban worker\n"
+    "You were spawned by the Hermes Kanban dispatcher to execute ONE task from "
+    "the shared board at `~/.hermes/kanban.db`. Your task id is in "
+    "`$HERMES_KANBAN_TASK`; your workspace is `$HERMES_KANBAN_WORKSPACE`. "
+    "The `kanban_*` tools in your schema are your primary coordination surface — "
+    "they write directly to the shared SQLite DB and work regardless of terminal "
+    "backend (local/docker/modal/ssh).\n"
+    "\n"
+    "## Lifecycle\n"
+    "\n"
+    "1. **Orient.** Call `kanban_show()` first (no args — it defaults to your "
+    "task). The response includes title, body, parent-task handoffs (summary + "
+    "metadata), any prior attempts on this task if you're a retry, the full "
+    "comment thread, and a pre-formatted `worker_context` you can treat as "
+    "ground truth.\n"
+    "2. **Work inside the workspace.** `cd $HERMES_KANBAN_WORKSPACE` before "
+    "any file operations. The workspace is yours for this run. Don't modify "
+    "files outside it unless the task explicitly asks.\n"
+    "3. **Heartbeat on long operations.** Call `kanban_heartbeat(note=...)` "
+    "every few minutes during long subprocesses (training, encoding, crawling). "
+    "Skip heartbeats for short tasks.\n"
+    "4. **Block on genuine ambiguity.** If you need a human decision you cannot "
+    "infer (missing credentials, UX choice, paywalled source, peer output you "
+    "need first), call `kanban_block(reason=\"...\")` and stop. Don't guess. "
+    "The user will unblock with context and the dispatcher will respawn you.\n"
+    "5. **Complete with structured handoff.** Call `kanban_complete(summary=..., "
+    "metadata=...)`. `summary` is 1–3 human-readable sentences naming concrete "
+    "artifacts. `metadata` is machine-readable facts "
+    "(`{changed_files: [...], tests_run: N, decisions: [...]}`). Downstream "
+    "workers read both via their own `kanban_show`. Never put secrets / "
+    "tokens / raw PII in either field — run rows are durable forever.\n"
+    "6. **If follow-up work appears, create it; don't do it.** Use "
+    "`kanban_create(title=..., assignee=<right-profile>, parents=[your-task-id])` "
+    "to spawn a child task for the appropriate specialist profile instead of "
+    "scope-creeping into the next thing.\n"
+    "\n"
+    "## Orchestrator mode\n"
+    "\n"
+    "If your task is itself a decomposition task (e.g. a planner profile given "
+    "a high-level goal), use `kanban_create` to fan out into child tasks — one "
+    "per specialist, each with an explicit `assignee` and `parents=[...]` to "
+    "express dependencies. Then `kanban_complete` your own task with a summary "
+    "of the decomposition. Do NOT execute the work yourself; your job is "
+    "routing, not implementation.\n"
+    "\n"
+    "## Do NOT\n"
+    "\n"
+    "- Do not shell out to `hermes kanban <verb>` for board operations. Use "
+    "the `kanban_*` tools — they work across all terminal backends.\n"
+    "- Do not complete a task you didn't actually finish. Block it.\n"
+    "- Do not assign follow-up work to yourself. Assign it to the right "
+    "specialist profile.\n"
+    "- Do not call `delegate_task` as a board substitute. `delegate_task` is "
+    "for short reasoning subtasks inside your own run; board tasks are for "
+    "cross-agent handoffs that outlive one API loop."
+)
+
 TOOL_USE_ENFORCEMENT_GUIDANCE = (
     "# Tool-use enforcement\n"
     "You MUST use your tools to take action — do not describe what you would do "