fix: larger toolbar buttons, text field grows with the text (Issues #35, #34, #28)

- Toolbar: 2 px gaps and 3 px dividers instead of 3 px and 7 px, and the
  size estimate now matches the measured layout exactly. On a 900 px
  screen the buttons are back to 30 px despite the new view-only button.
- Text tool: a new field starts three letters wide and grows with the
  longest line up to the wrap width at the page edge.
- INK_NOTES_DEBUG_FLING now confirms it is active and logs every finger
  lift, including touches ignored because the pen is near.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/main.rs

@@ -1426,6 +1426,11 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     let mut touch_pan_last_pos = (0.0_f32, 0.0_f32);
     // Nachgleiten nach schnellem Wischen mit dem Finger (Issue #28)
     let mut fling = ink_notes::viewport::Fling::default();
+    // Diagnosis for Issue #28: log every finger lift and the swipe speed
+    let debug_fling = std::env::var_os("INK_NOTES_DEBUG_FLING").is_some();
+    if debug_fling {
+        eprintln!("[Nachgleiten] Diagnose aktiv – bitte mit dem Finger wischen");
+    }
 
     // Stylus / Digitizer Zustand (Octotablet / Wayland Tablet Protocol)
     let mut is_stylus_drawing = false;
@@ -2843,6 +2848,9 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
 
                         // Hardware-Palm-Rejection: Wenn der Stylus in Proximity ist oder zeichnet, Touch ignorieren
                         if is_stylus_drawing || is_stylus_in_proximity {
+                            if debug_fling && touch.phase != TouchPhase::Moved {
+                                eprintln!("[Nachgleiten] Finger ignoriert ({:?}): Stift in der Nähe", touch.phase);
+                            }
                             return;
                         }
 
@@ -3058,6 +3066,14 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
                             TouchPhase::Ended | TouchPhase::Cancelled => {
                                 active_touches.remove(&touch.id);
                                 long_press.cancel();
+                                if debug_fling {
+                                    eprintln!(
+                                        "[Nachgleiten] Finger abgehoben ({:?}), verschiebt: {}, weitere Finger: {}",
+                                        touch.phase,
+                                        is_touch_panning,
+                                        active_touches.len()
+                                    );
+                                }
 
                                 if active_touches.is_empty() {
                                     is_pinch_gesturing = false;
@@ -3069,7 +3085,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
                                         canvas.pan(dx, dy);
                                         fling.track(Vec2::new(dx, dy), Instant::now());
                                         let velocity = fling.release(Instant::now());
-                                        if std::env::var_os("INK_NOTES_DEBUG_FLING").is_some() {
+                                        if debug_fling {
                                             eprintln!(
                                                 "[Nachgleiten] {:.0} px/s beim Abheben, gleitet: {}",
                                                 velocity.length(),

src/text.rs

@@ -151,6 +151,20 @@ impl TextBox {
         glam::Vec2::new(self.wrap_width.max(self.size), self.layout().height())
     }
 
+    /// Width of the field while it is being edited: as wide as the longest line plus room for
+    /// the next character, at most the wrap width, so a new field starts short (Issue #34).
+    pub fn edit_width(&self) -> f32 {
+        let widest = self
+            .layout()
+            .lines
+            .iter()
+            .map(|line| line.width)
+            .fold(0.0, f32::max);
+        (widest + self.size)
+            .max(3.0 * self.size)
+            .min(self.wrap_width.max(self.size))
+    }
+
     /// Setzt den Text mit Zeilenumbruch an Leerzeichen; zu lange Wörter werden zeichenweise
     /// umbrochen, Zeilenumbrüche im Text bleiben erhalten.
     pub fn layout(&self) -> TextLayout {
@@ -409,6 +423,19 @@ mod tests {
         TextBox::new(content.to_string(), 50.0, TextFont::Sans, wrap_width)
     }
 
+    #[test]
+    fn test_edit_width_grows_with_the_text() {
+        let empty = sample("", 1500.0);
+        assert!((empty.edit_width() - 150.0).abs() < 1e-3);
+        let short = sample("Hallo", 1500.0);
+        let longer = sample("Hallo Welt, wie geht es", 1500.0);
+        assert!(short.edit_width() < longer.edit_width());
+        assert!(longer.edit_width() < 1500.0);
+        // Long text wraps at the page edge and fills the full width
+        let long = sample(&"Wort ".repeat(100), 1500.0);
+        assert!((long.edit_width() - 1500.0).abs() < 1e-3);
+    }
+
     #[test]
     fn test_fonts_load() {
         for font in [TextFont::Sans, TextFont::Mono] {

src/ui.rs

@@ -639,13 +639,16 @@ impl UiState {
 
     /// Länge der längsten Farbpalette; so viel Platz hält die Leiste immer frei.
     pub const MAX_PALETTE_LEN: usize = 5;
+    /// Vertical gap between toolbar buttons and the height of a divider line.
+    pub const SIDEBAR_SPACING: f32 = 2.0;
+    pub const SIDEBAR_DIVIDER: f32 = 3.0;
 
     /// Durchmesser der Farbtupfer passend zur Knopfgröße.
     pub fn sidebar_swatch_size(button_size: f32) -> f32 {
         button_size - 10.0
     }
 
-    /// Größte Knopfgröße (40 px, schrittweise bis 28 px), bei der die Leiste mit allen Elementen
+    /// Größte Knopfgröße (40 px, schrittweise bis 26 px), bei der die Leiste mit allen Elementen
     /// des aktiven Werkzeugs in `max_height` passt. `continuous`: durchgehende Ansicht (ohne
     /// Blätterpfeile).
     pub fn sidebar_button_size(tool: ActiveTool, max_height: f32, continuous: bool) -> f32 {
@@ -655,11 +658,11 @@ impl UiState {
         let page_buttons = if continuous { 2 } else { 4 };
         let buttons = 12 + page_buttons + if select { 4 } else { 0 };
         let dividers = 5 + usize::from(select);
-        let spacing = 3.0;
+        let spacing = Self::SIDEBAR_SPACING;
         let needed = |b: f32| {
             buttons as f32 * (b + spacing)
                 + Self::MAX_PALETTE_LEN as f32 * (Self::sidebar_swatch_size(b) + spacing)
-                + dividers as f32 * (7.0 + spacing)
+                + dividers as f32 * (Self::SIDEBAR_DIVIDER + spacing)
                 // frame, margins and the spacing egui adds (measured with the selection tool)
                 + 40.0
         };
@@ -1092,8 +1095,10 @@ fn sidebar_button(
 
 /// Waagerechte Trennlinie zwischen Gruppen der Werkzeugleiste.
 fn sidebar_divider(ui: &mut egui::Ui, button_size: f32) {
-    let (rect, _) =
-        ui.allocate_exact_size(egui::vec2(button_size - 12.0, 7.0), egui::Sense::hover());
+    let (rect, _) = ui.allocate_exact_size(
+        egui::vec2(button_size - 12.0, UiState::SIDEBAR_DIVIDER),
+        egui::Sense::hover(),
+    );
     ui.painter().hline(
         rect.x_range(),
         rect.center().y,
@@ -1502,7 +1507,7 @@ fn text_edit_overlay(ctx: &egui::Context, state: &mut UiState) {
     // anpassen, damit die Zeilen an denselben Stellen umbrechen wie auf dem Blatt
     let height_px = font_size * ctx.pixels_per_point() * edit.text.font.height_per_em();
     let rounding = height_px.round().max(1.0) / height_px;
-    let width = (edit.text.wrap_width.max(edit.text.size) * sx * view.scale * rounding).max(8.0);
+    let width = (edit.text.edit_width() * sx * view.scale * rounding).max(8.0);
     let color = color32_from(if adapt {
         adapt_ink_color(edit.color)
     } else {
@@ -3004,7 +3009,7 @@ pub fn render_ui(
                             // Zentriertes Layout nimmt sonst die volle Fensterbreite ein
                             ui.set_width(btn);
                             ui.with_layout(egui::Layout::top_down(egui::Align::Center), |ui| {
-                                ui.spacing_mut().item_spacing = egui::vec2(0.0, 3.0);
+                                ui.spacing_mut().item_spacing = egui::vec2(0.0, UiState::SIDEBAR_SPACING);
 
                                 // --- Notizbücher ---
                                 let doc_tooltip = t!(