feat: hide Orch tab when orchestration is not enabled

- serveIndex injects <script>var ORCH_ENABLED=true;</script> before
  </head> when orchBroadcaster is non-nil (i.e. --orchestration active)
- JS hides the Orch tab button and panel when ORCH_ENABLED is falsy,
  and sets --tab-count CSS var to 6 so the indicator pill stays correct
- tab indicator width uses var(--tab-count, 7) — defaults to 7 when
  orchestration is enabled, falls back to 6 otherwise
- No extra API endpoint or network request needed

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

pkg/miniapp/miniapp.go

@@ -5,6 +5,7 @@ import (
 	"net/http"
 	"net/http/httputil"
 	"net/url"
+	"strings"
 	"sync"
 
 	"github.com/sipeed/picoclaw/pkg/orch"
@@ -86,6 +87,9 @@ func (h *Handler) serveIndex(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	w.Header().Set("Content-Type", "text/html; charset=utf-8")
+	if h.orchBroadcaster != nil {
+		data = []byte(strings.Replace(string(data), "</head>", "<script>var ORCH_ENABLED=true;</script></head>", 1))
+	}
 	w.Write(data)
 }
 

pkg/miniapp/static/index.html

@@ -84,7 +84,7 @@
     top: 2px;
     bottom: 2px;
     left: 2px;
-    width: calc(100%/7 - 2px);
+    width: calc(100% / var(--tab-count, 7) - 2px);
     border-radius: 8px;
     background: var(--tab-pill-bg);
     box-shadow: 0 0.5px 2px rgba(0,0,0,0.12), 0 0.5px 1px rgba(0,0,0,0.08);
@@ -941,8 +941,17 @@ let initData = tg.initData || '';
 let selectedSkill = null;
 var lastSSE = { plan: 0, skills: 0, session: 0, dev: 0 };
 
+// Hide Orch tab when orchestration is not enabled (ORCH_ENABLED injected by server).
+if (!window.ORCH_ENABLED) {
+  var orchTabBtn = document.querySelector('.tab[data-panel="orch"]');
+  var orchPanel  = document.getElementById('orch');
+  if (orchTabBtn) orchTabBtn.style.display = 'none';
+  if (orchPanel)  orchPanel.style.display  = 'none';
+  document.documentElement.style.setProperty('--tab-count', '6');
+}
+
 // Tab switching — re-fetch data unless SSE delivered recently
-const tabs = document.querySelectorAll('.tab');
+const tabs = document.querySelectorAll('.tab:not([style*="display: none"])');
 const tabIndicator = document.querySelector('.tab-indicator');
 
 function moveIndicator(index) {