Bug Description

When the Hermes/OpenClaw agent fires a `/reset` (or `/new`) command, the agent framework correctly emits a `on_session_reset` hook via `_notify_session_boundary("on_session_reset")`. However, the `@vectorize-io/hindsight-openclaw` plugin only subscribes to 4 hooks:

```
before_dispatch
before_agent_start
before_prompt_build
agent_end
```

`on_session_reset` and `on_session_finalize` are not subscribed. As a result, all session-scoped in-memory state in the plugin persists across resets:

Steps to Reproduce

1. Have Hindsight plugin active with `autoRetain: true`
2. Have a multi-turn conversation that gets retained to Hindsight
3. Run `/reset` in the agent (or `/new` — same code path)
4. Continue a new, unrelated conversation
5. Observe that previous turns are retained again under the new session (duplicate entries)
6. Alternatively: observe turn counting is off because `turnCountBySession` never resets

Expected Behavior

When `/reset` fires, the Hindsight plugin should clear all session-scoped state, either by:

• Subscribing to the `on_session_reset` hook and clearing its Maps there
• Subscribing to `on_session_finalize` (which is also emitted by Hermes on full session end)
• Providing a `reset()` / `clearSessionState()` method that Hermes calls on reset

Root Cause Analysis

The OpenClaw plugin architecture defines session boundary hooks (`on_session_reset`, `on_session_finalize`) but the Hindsight plugin never subscribes to them. The plugin only handles per-turn retain via `agent_end` and recall via `before_prompt_build`, with no concept of session lifecycle.

Additionally, `shutdown_memory_provider()` is only called on true session end (not on reset), so `on_session_end()` is never triggered either.

Environment

• hindsight-openclaw: 0.6.6
• @vectorize-io/hindsight-all: ^0.1.0
• @vectorize-io/hindsight-client: ^0.5.0
• Hermes Agent (OpenClaw-compatible)

Suggested Fix

In `hindsight-integrations/openclaw/src/index.ts`:

1. Subscribe to `on_session_reset`:

```ts
api.on("on_session_reset", async (event: any, ctx?: PluginHookAgentContext) => {
const sessionKey = ctx?.sessionKey ?? event?.sessionKey;
if (sessionKey) {
turnCountBySession.delete(sessionKey);
documentSequenceBySession.delete(sessionKey);
sessionIdentityBySession.delete(sessionKey);
skipHindsightTurnBySession.delete(sessionKey);
}
});
```

2. Also subscribe to `on_session_finalize` for proper cleanup on true session end.

3. (Hermes Agent side) Consider calling `shutdown_memory_provider()` on reset as well, not only on true session end, so `on_session_end()` fires too.