feat(ui): NEXUSMON operator-grade shell — app.py

app.py

@@ -3,6 +3,7 @@
 Public ritual space. Part of the Nexusmon sovereign AI organism.
 """
 from __future__ import annotations
+import base64
 import time
 from pathlib import Path
 import gradio as gr
@@ -11,11 +12,37 @@ ORG_URL = "https://huggingface.co/Nexusmon"
 FRONT_DOOR_URL = "https://huggingface.co/spaces/Nexusmon/README"
 RANKING_URL = "https://huggingface.co/spaces/Nexusmon/hf-nexusmon-ranking"
 KNOWLEDGE_URL = "https://huggingface.co/spaces/Nexusmon/hf-nexusmon-knowledge"
+PRESENCE_BANNER = "nexusmon-presence.svg"
+
+def _presence_banner_src() -> str | None:
+    candidates = [
+        Path(__file__).resolve().parent / "assets" / PRESENCE_BANNER,
+        Path(__file__).resolve().parents[4] / "assets" / PRESENCE_BANNER,
+    ]
+    for candidate in candidates:
+        if candidate.is_file():
+            encoded = base64.b64encode(candidate.read_bytes()).decode("ascii")
+            return f"data:image/svg+xml;base64,{encoded}"
+    return None
 
 def build() -> str:
     now = time.strftime("%Y-%m-%d %H:%M UTC", time.gmtime())
+    banner_src = _presence_banner_src()
+    if banner_src:
+        banner = f"""
+        <div class="nx-presence-frame" style="margin-bottom: 1rem; padding: 0.7rem; border: 1px solid rgba(255,255,255,0.08); border-radius: 24px; background: rgba(255,255,255,0.02); box-shadow: 0 18px 44px rgba(0, 0, 0, 0.28);">
+          <img src="{banner_src}" alt="NEXUSMON presence banner" style="display:block;width:100%;height:auto;border-radius:18px;" />
+        </div>
+        """.strip()
+    else:
+        banner = """
+        <div class="nx-presence-frame" style="margin-bottom: 1rem; padding: 1rem 1.2rem; border: 1px solid rgba(255,255,255,0.08); border-radius: 24px; background: rgba(255,255,255,0.02); color: #8fefff; text-transform: uppercase; letter-spacing: 0.22em; font-size: 0.72rem;">
+          NEXUSMON presence banner unavailable
+        </div>
+        """.strip()
     return f"""
     <div class="nx-root">
+      {banner}
       <header class="nx-header">
         <div class="nx-header-left">
           <span class="nx-eyebrow">NEXUSMON / public ritual space</span>