Download MD no histórico, relatórios externos e service systemd

- Botão de download .md no modal de detalhe do histórico (agente e pipeline)
- Relatórios de execução gravados também em ~/agent_reports/ (configurável via AGENT_REPORTS_DIR)
- Service systemd (user) para iniciar o orchestrator no boot com auto-restart

public/css/styles.css

@@ -2813,6 +2813,118 @@ tbody tr:hover td {
   margin-top: 4px;
 }
 
+.dropzone {
+  border: 2px dashed var(--border-secondary);
+  border-radius: 10px;
+  padding: 20px;
+  text-align: center;
+  transition: all 0.2s;
+  cursor: pointer;
+  background: var(--bg-primary);
+}
+
+.dropzone:hover,
+.dropzone.dragover {
+  border-color: var(--accent);
+  background: rgba(139, 92, 246, 0.05);
+}
+
+.dropzone-content {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  gap: 6px;
+  color: var(--text-muted);
+}
+
+.dropzone-content i,
+.dropzone-content svg {
+  width: 28px;
+  height: 28px;
+  color: var(--text-muted);
+  opacity: 0.6;
+}
+
+.dropzone-content p {
+  font-size: 13px;
+  margin: 0;
+}
+
+.dropzone-browse {
+  background: none;
+  border: none;
+  color: var(--accent);
+  cursor: pointer;
+  font-size: 13px;
+  text-decoration: underline;
+  padding: 0;
+}
+
+.dropzone-hint {
+  font-size: 11px;
+  color: var(--text-muted);
+  opacity: 0.7;
+}
+
+.dropzone-list {
+  list-style: none;
+  padding: 0;
+  margin: 8px 0 0;
+  display: flex;
+  flex-direction: column;
+  gap: 4px;
+}
+
+.dropzone-list:empty {
+  display: none;
+}
+
+.dropzone-list + .dropzone-content {
+  display: none;
+}
+
+.dropzone-file {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  padding: 6px 10px;
+  background: var(--bg-secondary);
+  border-radius: 6px;
+  font-size: 12px;
+}
+
+.dropzone-file-name {
+  flex: 1;
+  min-width: 0;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+  color: var(--text-primary);
+  text-align: left;
+}
+
+.dropzone-file-size {
+  color: var(--text-muted);
+  font-size: 11px;
+  flex-shrink: 0;
+}
+
+.dropzone-file-remove {
+  background: none;
+  border: none;
+  color: var(--text-muted);
+  cursor: pointer;
+  padding: 2px;
+  line-height: 1;
+  border-radius: 4px;
+  flex-shrink: 0;
+}
+
+.dropzone-file-remove:hover {
+  color: var(--error);
+  background: rgba(239, 68, 68, 0.1);
+}
+
 .form-actions {
   display: flex;
   gap: 8px;