initial commit — cassandra v0.1

Containerised macro-strategy dashboard: 4-panel web UI (indicators,
portfolio, flash news, AI strategic log), MariaDB store, hourly
ingestion jobs, OpenRouter-backed AI analysis.

Ports the four prototype scripts in the parent dir (market_pulse,
flash_news, trading212, strategic_log) into async services backed by a
persistent DB and served via FastAPI + Jinja2 + HTMX. APScheduler runs
as a separate compose service for crash-safety and easier restarts.

Portfolio composition + position names come live from Trading 212;
news per-ticker headlines reuse those names. Tone (NOVICE/INTERMEDIATE/
PRO) and analysis style (DRY/SPECULATIVE) are env-configurable and
stored on each log row so historical entries show what produced them.

Default model is deepseek/deepseek-v4-flash (overridable via env).
Light/dark theme toggle, sans-serif for prose surfaces, monospace for
data. Bearer-token auth, OpenRouter monthly cost cap, RSS feeds auto-
disabled on consecutive failures.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

app/static/js/chat.js

@@ -0,0 +1,73 @@
+// Cassandra chat sidebar — ephemeral, client-state conversation.
+// No persistence: page refresh starts a new chat.
+(() => {
+  const thread = document.getElementById('chat-thread');
+  const form   = document.getElementById('chat-form');
+  const input  = document.getElementById('chat-input');
+  const send   = document.getElementById('chat-send');
+  if (!thread || !form || !input || !send) return;
+
+  /** @type {{role: string, content: string}[]} */
+  const messages = [];
+
+  function escapeHTML(s) {
+    return s.replace(/&/g, '&')
+            .replace(/</g, '&lt;')
+            .replace(/>/g, '&gt;');
+  }
+
+  function append(role, html_or_text, opts) {
+    const div = document.createElement('div');
+    div.className = 'chat-msg chat-msg--' + role;
+    if (opts && opts.html) {
+      div.innerHTML = html_or_text;
+    } else {
+      div.textContent = html_or_text;
+    }
+    thread.appendChild(div);
+    thread.scrollTop = thread.scrollHeight;
+    return div;
+  }
+
+  form.addEventListener('submit', async (e) => {
+    e.preventDefault();
+    const text = input.value.trim();
+    if (!text || send.disabled) return;
+    messages.push({role: 'user', content: text});
+    append('user', text);
+    input.value = '';
+    send.disabled = true;
+    const thinking = append('assistant pending', '…');
+    try {
+      const r = await fetch('/api/chat', {
+        method: 'POST',
+        headers: {'Content-Type': 'application/json'},
+        body: JSON.stringify({messages}),
+      });
+      if (!r.ok) {
+        const msg = await r.text();
+        thinking.className = 'chat-msg chat-msg--error';
+        thinking.textContent = 'HTTP ' + r.status + ': ' + msg.slice(0, 300);
+        return;
+      }
+      const data = await r.json();
+      thinking.className = 'chat-msg chat-msg--assistant';
+      thinking.innerHTML = data.content_html || escapeHTML(data.content);
+      messages.push({role: 'assistant', content: data.content});
+    } catch (err) {
+      thinking.className = 'chat-msg chat-msg--error';
+      thinking.textContent = 'error: ' + err.message;
+    } finally {
+      send.disabled = false;
+      input.focus();
+    }
+  });
+
+  // Enter to send; Shift+Enter for newline.
+  input.addEventListener('keydown', (e) => {
+    if (e.key === 'Enter' && !e.shiftKey) {
+      e.preventDefault();
+      form.requestSubmit();
+    }
+  });
+})();