System prompt: build from agent persona/instructions, store in chain, remove UI textarea

wwwroot/js/api.js

@@ -1,10 +1,10 @@
 // ── API Calls ──
 
-async function apiChat(messages, systemPrompt, sessionId) {
+async function apiChat(messages, sessionId) {
   return fetch('/api/chat', {
     method: 'POST',
     headers: { 'Content-Type': 'application/json' },
-    body: JSON.stringify({ messages, systemPrompt, sessionId })
+    body: JSON.stringify({ messages, sessionId })
   });
 }
 

wwwroot/js/chat.js

@@ -21,7 +21,6 @@ async function clearChat() {
 async function sendMessage() {
   const input = $('#input');
   const btn = $('#send');
-  const systemPrompt = $('#systemPrompt').value.trim();
   const text = input.value.trim();
   if (!text) return;
 
@@ -38,7 +37,7 @@ async function sendMessage() {
   let currentToolBox = null;
 
   try {
-    const resp = await apiChat(messages, systemPrompt, getCurrentSessionId());
+    const resp = await apiChat(messages, getCurrentSessionId());
     const reader = resp.body.getReader();
     const decoder = new TextDecoder();
     let buffer = '';

wwwroot/js/pages/chat-page.js

@@ -27,15 +27,6 @@ registerPage('chat', {
       backBtn.addEventListener('click', () => navigateTo('session', { id: sessionId }));
     }
 
-    // System Prompt Toggle
-    const showSystem = document.getElementById('showSystem');
-    const systemPrompt = document.getElementById('systemPrompt');
-    if (showSystem && systemPrompt) {
-      showSystem.addEventListener('change', () => {
-        systemPrompt.classList.toggle('visible', showSystem.checked);
-      });
-    }
-
     // Send
     const sendBtn = document.getElementById('send');
     if (sendBtn) sendBtn.addEventListener('click', sendMessage);