feat(token-viz): Phase 1 — token budget panel with color bar and breakdown table

gui_2.py

@@ -296,6 +296,8 @@ class App:
   self._token_budget_current = 0
   self._token_budget_limit = 0
   self._gemini_cache_text = ""
+  self._last_stable_md: str = ''
+  self._token_stats: dict = {}
   self.ui_disc_truncate_pairs: int = 2
   self.ui_auto_scroll_comms = True
   self.ui_auto_scroll_tool_calls = True
@@ -552,6 +554,7 @@ class App:
     start_time = time.time()
     try:
      md, path, file_items, stable_md, disc_text = self._do_generate()
+     self._last_stable_md = stable_md
      self.last_md = md
      self.last_md_path = path
      self.last_file_items = file_items
@@ -1222,6 +1225,7 @@ class App:
   """Logic for the 'Gen + Send' action."""
   try:
    md, path, file_items, stable_md, disc_text = self._do_generate()
+   self._last_stable_md = stable_md
    self.last_md = md
    self.last_md_path = path
    self.last_file_items = file_items
@@ -1373,6 +1377,7 @@ class App:
     self._token_budget_pct = stats.get("percentage", 0.0) / 100.0
     self._token_budget_current = stats.get("current", 0)
     self._token_budget_limit = stats.get("limit", 0)
+    self._token_stats = stats
    except Exception:
     pass
   threading.Thread(target=fetch_stats, daemon=True).start()
@@ -2720,11 +2725,47 @@ class App:
   if usage["cache_read_input_tokens"]:
    imgui.text_colored(C_LBL, f"  Cache Read: {usage['cache_read_input_tokens']:,}  Creation: {usage['cache_creation_input_tokens']:,}")
   imgui.text("Token Budget:")
-  imgui.progress_bar(self._token_budget_pct, imgui.ImVec2(-1, 0), f"{self._token_budget_current:,} / {self._token_budget_limit:,}")
+  imgui.separator()
+  imgui.text("Token Budget")
+  self._render_token_budget_panel()
   if self._gemini_cache_text:
    imgui.text_colored(C_SUB, self._gemini_cache_text)
 
- def _render_message_panel(self) -> None:
+ def _render_token_budget_panel(self) -> None:
+  stats = self._token_stats
+  if not stats:
+   imgui.text_disabled("Token stats unavailable")
+   return
+  pct = stats.get("utilization_pct", 0.0)
+  current = stats.get("estimated_prompt_tokens", 0)
+  limit = stats.get("max_prompt_tokens", 0)
+  headroom = stats.get("headroom_tokens", 0)
+  if pct < 50.0:
+   color = imgui.ImVec4(0.2, 0.8, 0.2, 1.0)
+  elif pct < 80.0:
+   color = imgui.ImVec4(1.0, 0.8, 0.0, 1.0)
+  else:
+   color = imgui.ImVec4(1.0, 0.2, 0.2, 1.0)
+  imgui.push_style_color(imgui.Col_.plot_histogram, color)
+  imgui.progress_bar(pct / 100.0, imgui.ImVec2(-1, 0), f"{pct:.1f}%")
+  imgui.pop_style_color()
+  imgui.text_disabled(f"{current:,} / {limit:,} tokens  ({headroom:,} remaining)")
+  sys_tok = stats.get("system_tokens", 0)
+  tool_tok = stats.get("tools_tokens", 0)
+  hist_tok = stats.get("history_tokens", 0)
+  total_tok = sys_tok + tool_tok + hist_tok or 1
+  if imgui.begin_table("token_breakdown", 3, imgui.TableFlags_.borders_inner_h | imgui.TableFlags_.sizing_fixed_fit):
+   imgui.table_setup_column("Component")
+   imgui.table_setup_column("Tokens")
+   imgui.table_setup_column("Pct")
+   imgui.table_headers_row()
+   for lbl, tok in [("System", sys_tok), ("Tools", tool_tok), ("History", hist_tok)]:
+    imgui.table_next_row()
+    imgui.table_set_column_index(0); imgui.text(lbl)
+    imgui.table_set_column_index(1); imgui.text(f"{tok:,}")
+    imgui.table_set_column_index(2); imgui.text(f"{tok / total_tok * 100:.0f}%")
+   imgui.end_table()
+
  # LIVE indicator
   is_live = self.ai_status in ["running powershell...", "fetching url...", "searching web...", "powershell done, awaiting AI..."]
   if is_live: