Plant assistant mockup: operator, management, sales

docs/plant-assistant.html (test site /demos/plant-assistant/): the
plant assistant on vinyl-ai as three roles see it. Operator at the C1
press kiosk in Thai or English with push to talk (non-fill rejects
explained from cycle rows, lot change and press hall humidity, the
stamper change procedure quoted from the approved version, a lot on
hold, a refused price question, a safety question answered word for
word); management at a desk (output and yield per press against the
plan basis, steam per record against scale.md, orders at risk, the
weekly note, payroll refused); sales on a phone (order status and ship
window, repress feasibility from archived mothers and the standby
calendar, repress leads, a test pressing status, fans' addresses
refused). Each answer carries numbered sources; the side panel shows
the tool calls (ERPNext as the asker's role, the PostgreSQL replica,
VictoriaMetrics, documents, event log) on premises with the internet
not used; action buttons create drafts only. Deep links
#role=<role>&q=<id>, light and dark theme. Invented data; names match
the factory console demo.

plant-assistant.md: mockup link; sales and customer service row in
"Who asks what"; sales drafts (quotation, CRM opportunity, message).
README, site index and site/build.sh link and publish the page.

site/public/index.html

@@ -148,6 +148,16 @@ document.documentElement.setAttribute("data-theme",t);})();
         pressed so far, lab and inspection results. Simulated data.</span>
       </a>
     </li>
+    <li>
+      <a href="demos/plant-assistant/">
+        <strong>Plant assistant, vinyl-ai (mockup)</strong>
+        <span>Ask the plant: an operator at the press kiosk in Thai by push
+        to talk, management at a desk, sales on a phone. Every answer shows
+        its sources and the tool calls behind it, drafts records for a
+        person to submit, quotes safety steps word for word and refuses what
+        the asker may not see. Self-hosted on premises. Invented data.</span>
+      </a>
+    </li>
     <li>
       <a href="demos/order/">
         <strong>Order a record (step by step)</strong>