merge(13): AIUI source migrated in-repo — supersedes the two-repo split (D-15/D-18)

Brings AIUI's full 230-commit history under aiui/ via git subtree, plus main's
current head. Operator decision 2026-08-03: AIUI moves into this repo rather
than staying at git.tx1138.com. This also lands e30ac1d (13-01 Task 3), which
was stranded local-only while that remote was unreachable.

Plans 13-06, 13-09 and 13-11 still target /home/archipelago/Projects/AIUI paths
and must be re-planned against aiui/ before wave 2 runs.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

core/archipelago/src/api/rpc/federation/handlers.rs

@@ -51,10 +51,48 @@ impl RpcHandler {
     }
 }
 
+/// Error prefix the frontend keys on to know it should prompt for the node
+/// password and retry, rather than surface the message as a dead end.
+pub(in crate::api::rpc) const PASSWORD_REQUIRED_PREFIX: &str = "PASSWORD_REQUIRED";
+
 impl RpcHandler {
+    /// Re-authenticate the operator before granting `Trusted`.
+    ///
+    /// A Trusted peer can read node state, be deployed to, and is exempt from
+    /// the `!= Untrusted` gates federation/DWN/messaging use — so granting it
+    /// is a privilege escalation and must cost a fresh proof that the person
+    /// at the keyboard is the operator, not merely that a session cookie
+    /// exists. This is the same reasoning as `node.rotate-identity` and 2FA
+    /// setup, both of which already re-verify.
+    ///
+    /// Only ever called on the way UP. Demotion stays ungated: making
+    /// something less privileged must never be harder than leaving it alone,
+    /// or the safe action becomes the inconvenient one.
+    async fn verify_operator_password(&self, params: Option<&serde_json::Value>) -> Result<()> {
+        let password = params
+            .and_then(|p| p.get("password"))
+            .and_then(|v| v.as_str())
+            .unwrap_or("");
+
+        if password.is_empty() {
+            anyhow::bail!("{PASSWORD_REQUIRED_PREFIX}: node password required to grant Trusted");
+        }
+
+        if !self.auth_manager.verify_password(password).await? {
+            anyhow::bail!("Password verification failed");
+        }
+
+        Ok(())
+    }
+
     /// federation.invite — Generate an invite code containing our DID + onion for a peer.
     /// Optional param `trust_level`: "trusted" (default, "Link Your Nodes") or
     /// "observer" ("Invite a Peer") — the level BOTH sides assign for this invite.
+    ///
+    /// Minting a **Trusted** invite requires the node password (param
+    /// `password`): the invite is a bearer grant of Trusted to whoever
+    /// redeems it, so it is the escalation, not the later redemption.
+    /// Observer invites are unchanged.
     pub(in crate::api::rpc) async fn handle_federation_invite(
         &self,
         params: Option<serde_json::Value>,
@@ -71,6 +109,13 @@ impl RpcHandler {
             .transpose()?
             .unwrap_or(TrustLevel::Trusted);
 
+        // Note this covers the DEFAULT too: "Link Your Nodes" sends no
+        // `trust_level` and lands on Trusted above, so the gate must key off
+        // the resolved level rather than an explicit request for Trusted.
+        if trust_level == TrustLevel::Trusted {
+            self.verify_operator_password(params.as_ref()).await?;
+        }
+
         let (data, _) = self.state_manager.get_snapshot().await;
         let did = identity::did_key_from_pubkey_hex(&data.server_info.pubkey)?;
         let onion = data.server_info.tor_address.clone().unwrap_or_default();
@@ -272,6 +317,15 @@ impl RpcHandler {
                 if let Some(at) = &n.last_sync_error_at {
                     obj["last_sync_error_at"] = serde_json::json!(at);
                 }
+                // How this peer's trust level came to be. Emitted as an
+                // explicit null when unknown rather than omitted: "recorded
+                // before provenance was tracked" is the population the
+                // operator most needs to review, so the UI must be able to
+                // distinguish it from a field it simply didn't read.
+                obj["trust_source"] = match &n.trust_source {
+                    Some(src) => serde_json::to_value(src).unwrap_or(serde_json::Value::Null),
+                    None => serde_json::Value::Null,
+                };
                 obj
             })
             .collect();
@@ -323,6 +377,10 @@ impl RpcHandler {
     }
 
     /// federation.set-trust — Change trust level for a federated node.
+    ///
+    /// Promoting a node TO `Trusted` requires the node password (param
+    /// `password`). Demotion and no-op re-sets do not: see
+    /// `verify_operator_password` for why the gate is one-directional.
     pub(in crate::api::rpc) async fn handle_federation_set_trust(
         &self,
         params: Option<serde_json::Value>,
@@ -348,7 +406,32 @@ impl RpcHandler {
             ),
         };
 
-        federation::set_trust_level(&self.config.data_dir, did, trust).await?;
+        // Gate the ESCALATION only. Comparing against the node's current level
+        // means a re-set of an already-Trusted peer (the dropdown re-emitting
+        // its own value) doesn't pointlessly demand a password, while every
+        // path that actually raises a peer to Trusted does.
+        if trust == TrustLevel::Trusted {
+            let already_trusted = federation::load_nodes(&self.config.data_dir)
+                .await?
+                .iter()
+                .any(|n| n.did == did && n.trust_level == TrustLevel::Trusted);
+            if !already_trusted {
+                self.verify_operator_password(Some(&params)).await?;
+            }
+        }
+
+        // Stamp Manual: this is the one path where a human chose the level, so
+        // an audit of `trust_source` can tell it apart from the automatic
+        // grants that `UninvitedJoin` / `TransitiveMerge` mark.
+        federation::set_trust_level(
+            &self.config.data_dir,
+            did,
+            trust,
+            Some(federation::TrustSource::Manual),
+        )
+        .await?;
+
+        info!(did = %did, trust = %trust, "Operator set federation trust level");
 
         Ok(serde_json::json!({
             "updated": true,

core/archipelago/src/api/rpc/handshake.rs

@@ -350,10 +350,14 @@ impl RpcHandler {
                             // lands on Observer; keep this explicit demotion as a
                             // safety net for legacy Trusted-only invite codes — the
                             // discovery flow should never auto-trust.
+                            // `None` source: this is an automatic safety-net
+                            // demotion, not an operator decision, so it must
+                            // not overwrite how the peer actually got here.
                             let _ = crate::federation::set_trust_level(
                                 &self.config.data_dir,
                                 &node.did,
                                 crate::federation::TrustLevel::Observer,
+                                None,
                             )
                             .await;