fix(oracle-l8): close 3 polish caveats (dispatch labels / chat unread / leftrail leak)

Oracle PASS-with-caveats; closing all 3:

1. Wizard dispatch labels were 'human'/'agent'/'system' (impl-ish).
   Now 'Person'/'Assistant'/'System' in both the dropdown and the
   preview-pane badge.

2. Chat badge was thread COUNT (a buyer with 5 chats sees '5' forever).
   Now real unread count, computed locally from localStorage heads +
   read maps that the Chat scene already persists. App.tsx topbar
   poll still only fires 2 network calls (listThreads + workItems);
   per-thread unread math is zero-network.

3. LeftRail toast leaked 'POST /api/runtime/transactions/{id}/actions/
   submit' / save_draft. Rewritten as 'Switch to live mode and sign
   in to submit this action against EA2.'

Plus engineering-string sweep elsewhere: 'demo.flow-master.ai' /
'bundled JSON' / 'in-browser fetch' references removed from:
- App.tsx mode toggle title
- MissionControl loading spinner
- Landing mode-button title
- state/store snapshot toast
- data/live.ts + data/synthetic.ts tour-step bodies
- buildScenarios.ts tagline

Source-grep confirms no remaining user-visible engineering jargon
referencing the backend hostname or raw endpoints.

src/scenes/Chat.tsx

@@ -110,11 +110,16 @@ export default function Chat() {
     ).then((pairs) => {
       if (cancelled) return;
       const map: Record<string, ChatMessage | null> = {};
-      for (const [k, v] of pairs) map[k] = v;
+      const heads: Record<string, { at: string; by: string }> = {};
+      for (const [k, v] of pairs) {
+        map[k] = v;
+        if (v) heads[k] = { at: v.created_at, by: v.author_email };
+      }
       setPreviews(map);
+      try { localStorage.setItem(`fm.canvas.chat.heads.${me}`, JSON.stringify(heads)); } catch { /* ignore */ }
     });
     return () => { cancelled = true; };
-  }, [threads]);
+  }, [threads, me]);
 
   const unreadCount = useMemo(() => {
     let n = 0;

src/scenes/Landing.tsx

@@ -62,7 +62,7 @@ export default function Landing() {
               className={`btn btn-ghost btn-lg${mode === "live" ? " is-on" : ""}`}
               onClick={() => mode === "live" ? refreshLive() : setMode("live")}
               disabled={liveLoading}
-              title={mode === "live" ? "Re-fetch live scenarios from demo.flow-master.ai" : "Toggle between bundled snapshot and a live in-browser fetch"}
+              title={mode === "live" ? "Re-fetch live data from EA2" : "Switch to live mode"}
             >
               {liveLoading ? <span className="spin" /> : <Pulse size={13} />}
               {mode === "live" ? "Live · refresh" : "Go live"}

src/scenes/MissionControl.tsx

@@ -17,7 +17,7 @@ export default function MissionControl() {
     <div className="mc">
       {liveLoading && (
         <div className="mc-banner mc-banner-info">
-          <span className="spin" /> Fetching live scenarios from demo.flow-master.ai…
+          <span className="spin" /> Fetching live data from EA2…
         </div>
       )}
       {liveError && (

src/scenes/Wizard.tsx

@@ -281,7 +281,7 @@ export default function Wizard() {
                 <li key={n._key || i} className="wizard-preview-chain-item">
                   <span className="wizard-preview-chain-idx">{i + 1}</span>
                   <span className="wizard-preview-chain-name">{n.display_name || "Untitled step"}</span>
-                  <span className={`wizard-preview-chain-kind kind-${n.dispatch_kind || "human"}`}>{n.dispatch_kind || "human"}</span>
+                  <span className={`wizard-preview-chain-kind kind-${n.dispatch_kind || "human"}`}>{({ human: "Person", agent: "Assistant", system: "System" } as Record<string, string>)[n.dispatch_kind || "human"] || "Person"}</span>
                 </li>
               ))}
             </ol>
@@ -412,8 +412,8 @@ export default function Wizard() {
                           updateDraft({ nodes: newNodes });
                         }}
                       >
-                        <option value="human">Human</option>
-                        <option value="agent">Agent</option>
+                        <option value="human">Person</option>
+                        <option value="agent">Assistant</option>
                         <option value="system">System</option>
                       </select>
                       <div className="node-controls">