Add consent-gated media exchange library

docs/product-and-safety.md

@@ -47,6 +47,16 @@ Each subreddit snapshots a policy into a conversation when automation first hand
 
 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. Short refusals are interpreted in sequence: phrases such as “I’m good” become media boundaries only when they answer a media request.
 
+## Operator exchange media
+
+The exchange library contains only operator-uploaded images. Upload requires confirmation that every depicted adult consented to storage and bot delivery. Received conversation media is account-owned evidence and can never be promoted into this shared library.
+
+The bot may continue to ask another person for an optional photo under the configured conversation policy, but it must never mention, advertise, or offer an exchange-library image proactively. A library send requires a direct or indirect inbound image request. Exact anatomy requests match the operator-reviewed tags `penis`, `chest`, `selfie`, `topless`, or `feet`; the bot does not substitute a different anatomy when a match is unavailable.
+
+Nonspecific requests broaden progressively within one conversation. The first selects a random unused SFW asset, a later request may include topless/NSFW assets, and further requests may select from the full library. An asset is never selected twice in the same conversation, including after an uncertain send. After Matrix confirms the image event, the bot asks the other person to reciprocate without pressure. Missing inventory, failed delivery, changed conversation state, or an unconfirmed reciprocal message becomes an operator handoff.
+
+Reddit candidate eligibility remains the product's adult-entry assumption; this feature adds no separate verification workflow. Existing deterministic underage disclosures and conversation boundaries still stop automation before a library send.
+
 ## Success and analytics
 
 Do not collapse all progress into “messages sent.” Useful states include:
@@ -75,6 +85,6 @@ Read-only inspection, builds, tests, and documentation work do not grant any of
 
 ## Privacy and secrets
 
-Treat these as sensitive: `.env`, Reddit cookies, exported session JSON, Matrix access tokens, dashboard/agent tokens, the SQLite database, browser profiles, conversation text, usernames, private media, and logs that may contain request metadata.
+Treat these as sensitive: `.env`, Reddit cookies, exported session JSON, Matrix access tokens, dashboard/agent tokens, the SQLite database, browser profiles, conversation text, usernames, received private media, operator exchange media, and logs that may contain request metadata.
 
 Never commit or reproduce them in documentation, fixtures, logs, issue text, or tool output. Prefer redacted structural evidence. Production backups contain account and private conversation data and need the same protection as the live volume.