fix: page-named toolbar title + ellipsized needs-modules chip (0.21.1)

With no flow open the toolbar header said 'Kein Flow geöffnet' and
read as the page title (usertest finding); it now names the page
('Flows') while the empty state keeps the explanatory sentence. The
'needs N modules' chip ellipsizes in the narrow flow list instead of
overflowing its row on longer German labels.

Signed-off-by: flemming-it <sf@flemming.it>

CHANGELOG.md

@@ -4,6 +4,19 @@ All notable changes to `chain_studio_flow_editor` recorded here.
 Studio bumps its `pubspec.yaml` git ref to a specific release
 of this package on every editor change.
 
+## 0.21.1 — 2026-07-11
+
+### Fixed
+
+- **Toolbar names the page, not the missing state.** With no flow
+  open the header said "No flow open" / "Kein Flow geöffnet" — the
+  usertest read it as a confusing page title. It now says "Flows";
+  the state sentence stays in the centered empty state.
+- **"Needs N modules" chip no longer overflows the flow list.** The
+  label ellipsizes inside the narrow sidebar (the tooltip keeps the
+  full text); previously it tripped a RenderFlex overflow by a few
+  pixels on longer German labels.
+
 ## 0.21.0 — 2026-06-09
 
 ### Added