breadhelp 0.2.0: live guided tour overlay replacing static onboarding

Replaces the old in-window onboarding wizard with a real screen-wide
tour: dim + spotlight cutout around the actual on-screen component
(breadbar, breadbox), floating callout teaching the shortcut, and
event-driven confirmation via real Hyprland/breadd signals instead of
click-through fakery.

src/ui/tour/callout.rs

@@ -0,0 +1,135 @@
+//! The floating explanation bubble: title/body (rendered through the same
+//! constrained markdown subset guides use, so `[Show Keybind]`/`[Run]` tags
+//! work here too), dot progress, Back/Next. Positioned just below (or, if
+//! that would run off the bottom of the screen, above) the spotlighted
+//! target; a `Target::None` step gets no anchors at all, which wlr-layer-
+//! shell/gtk4-layer-shell centers on the monitor by convention.
+
+use gtk4::prelude::*;
+use gtk4::{Box as GBox, Button, Label, Orientation, Window};
+use gtk4_layer_shell::{Edge, KeyboardMode, Layer, LayerShell};
+
+use crate::content::keybinds::Keybind;
+use crate::content::markdown;
+use crate::content::tour::Step;
+
+use super::target::Rect;
+
+pub struct Callout {
+    pub window: Window,
+    pub back_btn: Button,
+    pub next_btn: Button,
+    pub skip_btn: Button,
+    pub demo_btn: Option<Button>,
+}
+
+const CALLOUT_WIDTH: i32 = 360;
+/// Rough height estimate used only to decide "does this fit below the
+/// target" before the widget has actually been laid out — doesn't need to
+/// be exact, just enough to avoid running off the bottom of the screen.
+const ESTIMATED_HEIGHT: i32 = 220;
+
+#[allow(clippy::too_many_arguments)]
+pub fn build(
+    monitor: &gdk4::Monitor,
+    rect: Option<Rect>,
+    monitor_size: (i32, i32),
+    step: &Step,
+    binds: &[Keybind],
+    step_index: usize,
+    total: usize,
+    is_last: bool,
+    confirmed: bool,
+    show_demo: bool,
+) -> Callout {
+    let window = Window::new();
+    window.set_decorated(false);
+    window.add_css_class("tour-window");
+    window.init_layer_shell();
+    window.set_layer(Layer::Overlay);
+    window.set_keyboard_mode(KeyboardMode::OnDemand);
+    window.set_monitor(Some(monitor));
+
+    if let Some(rect) = rect {
+        let (mon_w, mon_h) = monitor_size;
+        window.set_anchor(Edge::Left, true);
+        window.set_anchor(Edge::Top, true);
+        let margin_left = (rect.x).clamp(20, (mon_w - CALLOUT_WIDTH - 20).max(20));
+        let below = rect.y + rect.h + 12;
+        let margin_top = if below + ESTIMATED_HEIGHT <= mon_h {
+            below
+        } else {
+            (rect.y - 12 - ESTIMATED_HEIGHT).max(20)
+        };
+        window.set_margin(Edge::Left, margin_left);
+        window.set_margin(Edge::Top, margin_top);
+    }
+    // No anchors for a `Target::None` step — left to the compositor, which
+    // centers unanchored layer surfaces.
+
+    let root = GBox::new(Orientation::Vertical, 12);
+    root.add_css_class("tour-callout");
+    root.set_size_request(CALLOUT_WIDTH, -1);
+
+    let title = Label::new(Some(&step.title));
+    title.add_css_class("title");
+    title.set_xalign(0.0);
+    title.set_wrap(true);
+    root.append(&title);
+
+    let body = markdown::render(&markdown::parse(&step.body), binds);
+    root.append(&body);
+
+    if confirmed {
+        let done = Label::new(Some("\u{2713} Nice work — click Next to continue."));
+        done.add_css_class("tour-confirmed");
+        done.set_xalign(0.0);
+        root.append(&done);
+    }
+
+    let demo_btn = if show_demo {
+        let hint_row = GBox::new(Orientation::Horizontal, 8);
+        hint_row.add_css_class("tour-hint-row");
+        let hint_label = Label::new(Some("Still there?"));
+        hint_label.add_css_class("dim-label");
+        hint_label.set_hexpand(true);
+        hint_label.set_xalign(0.0);
+        let btn = Button::with_label("Show me");
+        hint_row.append(&hint_label);
+        hint_row.append(&btn);
+        root.append(&hint_row);
+        Some(btn)
+    } else {
+        None
+    };
+
+    // Text only, not a dot row too — a separate row of dots next to this
+    // said the identical thing twice with no added legibility.
+    let counter = Label::new(Some(&format!("Step {} of {total}", step_index + 1)));
+    counter.add_css_class("dim-label");
+    counter.set_xalign(0.0);
+    root.append(&counter);
+
+    let nav = GBox::new(Orientation::Horizontal, 8);
+    let skip_btn = Button::with_label("Skip tour");
+    skip_btn.add_css_class("flat");
+    let back_btn = Button::with_label("Back");
+    back_btn.set_sensitive(step_index > 0);
+    let spacer = GBox::new(Orientation::Horizontal, 0);
+    spacer.set_hexpand(true);
+    let next_btn = Button::with_label(if is_last { "Finish" } else { "Next" });
+    next_btn.add_css_class("suggested-action");
+    nav.append(&skip_btn);
+    nav.append(&spacer);
+    nav.append(&back_btn);
+    nav.append(&next_btn);
+    root.append(&nav);
+
+    window.set_child(Some(&root));
+    window.present();
+    if confirmed {
+        next_btn.grab_focus();
+    }
+
+    Callout { window, back_btn, next_btn, skip_btn, demo_btn }
+}