Add engagement-only conversation mode

docs/product-and-safety.md

@@ -46,11 +46,12 @@ Each subreddit snapshots a policy into a conversation when automation first hand
 | Mode | Meaning |
 | --- | --- |
 | `manual` | Never auto-reply; surface a human handoff. |
+| `engagement` | Send the normal opener, count the first verified reply as success, then complete without an automated response or human handoff. |
 | `legacy` | At most one optional autonomous media request, counting a request already present in the opener, followed by human handoff. |
 | `r4r` | Bounded rapport-style replies with autonomous safety checks. |
 | `r4r-media` | Rapport first, one bounded media ask, then a handoff/terminal boundary. |
 
-The snapshot matters: changing configuration later must not silently rewrite the rules for an active conversation. Automation stops for seller/upsell evidence, an image received, a detected boundary, unsafe content, an exhausted turn budget, a repeated media request, or a manual policy.
+The snapshot matters: changing configuration later must not silently rewrite the rules for an active conversation. Engagement mode marks the conversation and operator triage done as soon as the first post-opener inbound event is durably observed; it does not generate, claim, or send a reply. Other automation stops for seller/upsell evidence, an image received, a detected boundary, unsafe content, an exhausted turn budget, a repeated media request, or a manual policy.
 
 Within those boundaries, R4R replies are expected to participate naturally in consensual adult NSFW conversation instead of moralizing, declining the topic, or diverting ordinary flirting into generic small talk. In-character soft refusals are treated like provider refusals and fall through to the next configured chat model. This does not weaken recipient boundaries, the under-18 handoff, seller/off-platform controls, location and meeting prohibitions, or the separate media-request rules.