feat(automation): add isolated job delivery mode

README.md

@@ -373,8 +373,13 @@ hooks:
 
 Schedule automated messages on cron schedules. Each job fires an inbound message through the agent pipeline and routes the response to a configured output channel.
 
+Set `automation.delivery_mode` to control automation session behavior:
+- `shared_session` (default): reuse one session per cron job/webhook name.
+- `isolated_job`: create a fresh session per cron trigger/webhook request.
+
 ```yaml
 automation:
+  delivery_mode: shared_session
   cron:
     - name: daily-summary
       schedule: "0 9 * * *"            # 9 AM daily
@@ -399,6 +404,7 @@ automation:
 
 | Field | Required | Description |
 |-------|----------|-------------|
+| `automation.delivery_mode` | no | Automation session strategy: `shared_session` or `isolated_job` (default: `shared_session`) |
 | `name` | yes | Unique job identifier |
 | `schedule` | yes | Cron expression (standard 5-field) |
 | `message` | yes | Text sent to the agent when the job fires |
@@ -414,6 +420,7 @@ HTTP endpoints that trigger agent processing. Each webhook accepts POST requests
 
 ```yaml
 automation:
+  delivery_mode: shared_session
   webhooks:
     - name: github-push
       secret: "whsec_..."                  # HMAC secret for signature verification
@@ -435,6 +442,7 @@ Webhooks are available at `POST /webhooks/:name` on the gateway HTTP server. The
 
 | Field | Required | Description |
 |-------|----------|-------------|
+| `automation.delivery_mode` | no | Automation session strategy: `shared_session` or `isolated_job` (default: `shared_session`) |
 | `name` | yes | Unique webhook identifier (used in URL path) |
 | `secret` | no | HMAC secret for `X-Webhook-Signature` header verification (SHA-256) |
 | `message` | no | Template for the message sent to the agent (default: `{{body}}`) |