feat(messages): Phase 3 — editable-template composer, reply + create actions

The CRM action buttons and Reply now open a send-composer, not a silent
templated send.

- New send-composer (MessageComposer): loads the rendered template (via
  previewTemplate) or a reply stub into a fully-editable body — the admin can
  rewrite it or drop a note anywhere before sending. On send it goes out as-is
  (server-sanitized), no template re-render.
- Backend: emailProcessor.sendRawEmail() sends admin-edited HTML via the
  configured SMTP identity; POST /admin/email/send sanitizes + sends + records
  the message in email_queue as a 'manual' send.
- Migration 155: email_queue.origin ('system' default | 'manual'). The Sent
  stream now splits by origin — Automated ▸ Sent = system, Customers ▸ Sent =
  the human/edited messages (which finally populates that folder). /queue gains
  an origin filter + returns origin.
- Toolbar wired: Reply enabled on inbound customer mail (prefilled + quoted);
  Create Quote/Contract/Invoice open the composer with that template loaded;
  Gallery opens a blank compose. Accounting/Forward/Archive/Delete stay disabled
  (later phases). After send, jumps to Customers ▸ Sent.

Deferred to a later phase: two-way IMAP write-back; per-identity SMTP (manual
sends currently use the global from address). Frontend build + migration boot
verified.

backend/src/services/emailProcessor.js

@@ -772,6 +772,35 @@ async function sendTemplateEmail(to, templateKey, variables) {
   }
 }
 
+/**
+ * Send a fully-composed email (subject + HTML the admin already edited in the
+ * Messages composer) WITHOUT a template. Used for replies + human-sent document
+ * messages. Uses the configured SMTP identity + from address. Returns
+ * { messageId, html } so the caller can persist rendered_html for the record.
+ */
+async function sendRawEmail({ to, cc, subject, html, text, attachments } = {}) {
+  transporter = await initializeTransporter();
+  if (!transporter) throw new Error('Email service not configured');
+  const config = await db('email_configs').first();
+  if (!config || !config.from_email) throw new Error('Email service not configured');
+  const ccList = Array.isArray(cc) ? cc.filter(Boolean) : (cc ? [cc] : undefined);
+  const atts = Array.isArray(attachments)
+    ? attachments.filter((a) => a && (a.contentPath || a.path || a.content))
+        .map((a) => ({ filename: a.filename, path: a.contentPath || a.path, content: a.content, contentType: a.contentType }))
+    : undefined;
+  const info = await transporter.sendMail({
+    from: `${config.from_name} <${config.from_email}>`,
+    to,
+    cc: ccList,
+    subject,
+    html,
+    text: text || htmlToText(html),
+    attachments: atts,
+  });
+  logger.info(`Manual email sent: ${info.messageId}`);
+  return { messageId: info.messageId, html };
+}
+
 /**
  * Render a queued email's HTML WITHOUT sending it. Used by the Project
  * Overview cockpit to preview emails that predate the rendered_html column
@@ -1105,6 +1134,7 @@ module.exports = {
   initializeTransporter,
   startEmailQueueProcessor,
   sendTemplateEmail,
+  sendRawEmail,
   renderQueuedEmail,
   processEmailQueue,
   queueEmail,