feat: WebKit for web/html cells + display auto-discovery via heartbeat

Rust kiosk:
- web cells now use webkit6 WebView (load_uri)
- html cells use WebView.load_html (full HTML rendering)
- query_displays() reads /sys/class/drm/ for connected HDMI/DP outputs
- Heartbeat reports display geometry every 60s

Server:
- /api/kiosk/heartbeat accepts displays array
- Syncs kiosk-reported displays to display records
- Updates dimensions when changed, creates new displays for new ports

kiosk/Cargo.toml

@@ -32,3 +32,4 @@ hostname = "0.4"
 tokio-tungstenite = { version = "0.24", features = ["native-tls"] }
 futures-util = "0.3"
 url = "2"
+webkit6 = "0.4"

kiosk/src/server.rs

@@ -148,14 +148,18 @@ pub fn fetch_bundle(server: &str, key: &str) -> KioskBundle {
     resp.json().expect("bad bundle JSON")
 }
 
-/// Send heartbeat.
-pub fn heartbeat(server: &str, key: &str) {
+/// Send heartbeat with display geometry.
+pub fn heartbeat(server: &str, key: &str, displays: &[(String, u32, u32)]) {
     let client = reqwest::blocking::Client::new();
+    let display_info: Vec<_> = displays.iter().map(|(name, w, h)| {
+        serde_json::json!({ "name": name, "width_px": w, "height_px": h })
+    }).collect();
     let _ = client
         .post(format!("{server}/api/kiosk/heartbeat"))
         .header("Authorization", format!("Bearer {key}"))
         .json(&serde_json::json!({
             "kiosk_app_version": env!("CARGO_PKG_VERSION"),
+            "displays": display_info,
         }))
         .timeout(Duration::from_secs(5))
         .send();

kiosk/src/ui.rs

@@ -92,10 +92,11 @@ fn activate(app: &Application) {
             }
         });
 
-        // Heartbeat loop
+        // Heartbeat loop — also reports display geometry
         loop {
             std::thread::sleep(std::time::Duration::from_secs(60));
-            server::heartbeat(&server, &key);
+            let displays = query_displays();
+            server::heartbeat(&server, &key, &displays);
         }
     });
 
@@ -117,6 +118,33 @@ enum WorkerMsg {
     RenderBundle(KioskBundle),
 }
 
+/// Query connected HDMI displays from sysfs. Returns (name, width, height).
+/// Reads /sys/class/drm/*/status and /sys/class/drm/*/modes.
+fn query_displays() -> Vec<(String, u32, u32)> {
+    let mut out = Vec::new();
+    let Ok(entries) = std::fs::read_dir("/sys/class/drm") else { return out };
+    for entry in entries.flatten() {
+        let name = entry.file_name().to_string_lossy().to_string();
+        // Skip non-HDMI connectors and the "card" parents
+        if !name.contains("-HDMI-") && !name.contains("-DP-") { continue; }
+        let path = entry.path();
+        let status = std::fs::read_to_string(path.join("status")).unwrap_or_default();
+        if status.trim() != "connected" { continue; }
+        let modes = std::fs::read_to_string(path.join("modes")).unwrap_or_default();
+        // First line = preferred mode
+        let mode = modes.lines().next().unwrap_or("");
+        let parts: Vec<&str> = mode.split('x').collect();
+        if parts.len() != 2 { continue; }
+        let w: u32 = parts[0].parse().unwrap_or(0);
+        let h: u32 = parts[1].trim().parse().unwrap_or(0);
+        if w == 0 || h == 0 { continue; }
+        // Strip "cardN-" prefix for cleaner name
+        let clean_name = name.split_once('-').map(|(_, rest)| rest.to_string()).unwrap_or(name);
+        out.push((clean_name, w, h));
+    }
+    out
+}
+
 fn show_pairing_code(window: &ApplicationWindow, code: &str) {
     let vbox = GtkBox::new(Orientation::Vertical, 20);
     vbox.set_valign(gtk::Align::Center);
@@ -212,16 +240,20 @@ fn render_bundle(window: &ApplicationWindow, bundle: KioskBundle) {
                 }
             }
             "html" => {
-                let html = cell.html_content.as_deref().unwrap_or("HTML");
-                let label = Label::new(Some(&html.chars().take(100).collect::<String>()));
-                add_css(&label, "label { color: #888; background-color: #111; }");
-                label.set_vexpand(true);
-                label.set_hexpand(true);
-                label.upcast()
+                let html = cell.html_content.as_deref().unwrap_or("");
+                let webview = webkit6::WebView::new();
+                webkit6::prelude::WebViewExt::load_html(&webview, html, None);
+                webview.set_vexpand(true);
+                webview.set_hexpand(true);
+                webview.upcast()
             }
             "web" => {
                 let url = cell.web_url.as_deref().unwrap_or("about:blank");
-                placeholder(&format!("Web: {url}"))
+                let webview = webkit6::WebView::new();
+                webkit6::prelude::WebViewExt::load_uri(&webview, url);
+                webview.set_vexpand(true);
+                webview.set_hexpand(true);
+                webview.upcast()
             }
             _ => placeholder("Unknown content"),
         };

server/src/plugins/service-api-http/index.ts

@@ -226,6 +226,7 @@ function registerKioskRoutes(
       bundle_version?: string;
       kiosk_app_version?: string;
       os_version?: string;
+      displays?: Array<{ name: string; width_px: number; height_px: number }>;
     }>(event);
 
     repo.touchKiosk(kiosk.id, {
@@ -234,6 +235,29 @@ function registerKioskRoutes(
       os_version: body?.os_version ?? null,
     });
 
+    // Sync displays reported by the kiosk
+    if (Array.isArray(body?.displays)) {
+      const existing = repo.listDisplaysForKiosk(kiosk.id);
+      for (const reported of body.displays) {
+        const match = existing.find((d) => d.name.endsWith(reported.name));
+        if (match) {
+          if (match.width_px !== reported.width_px || match.height_px !== reported.height_px) {
+            repo.updateDisplay(match.id, {
+              width_px: reported.width_px,
+              height_px: reported.height_px,
+            } as any);
+          }
+        } else {
+          // New display — create it
+          repo.createDisplayForKiosk(kiosk.id, {
+            name: reported.name,
+            width_px: reported.width_px,
+            height_px: reported.height_px,
+          });
+        }
+      }
+    }
+
     return { ok: true, now: new Date().toISOString() };
   });