chore: public-readiness cleanup

- Remove default Grafana password (fail loudly if unset)
- Clean up stale delivery-proof TODO (already implemented at RPC layer)
- Document TUI send as local-only, point to REPL for E2E delivery
- Gitignore AI workflow files (CLAUDE.md, master-prompt.md, ai_team.py)
- Remove 5 orphaned v1 crates (bot, ffi, gen, gui, mobile)
- Commit ROADMAP.html updates

crates/quicproquo-server/src/domain/delivery.rs

@@ -97,7 +97,7 @@ impl DeliveryService {
 
         Ok(EnqueueResp {
             seq: first_seq,
-            delivery_proof: Vec::new(), // TODO: sign in Phase 2
+            delivery_proof: Vec::new(), // Proof generated at RPC handler layer (see v2_handlers/delivery.rs)
         })
     }