app icon: lynx (owner's ArtCraft drawing), Dock/taskbar/launcher wiring, palette docs

- assets/app-icon/: lightcraft.svg (master), lightcraft-small.svg, 1024 PNG, macOS 512 PNG,
  .icns, .ico, hicolor theme (ai.storyteller.lightcraft), LICENSE.txt, README (palette,
  geometry, provenance, files)
- packaging/icons.sh regenerates everything (resvg, iconutil, new `cargo xtask ico`)
- apps/lightcraft: runtime window/Dock icon + Wayland app id; build.rs embeds the .ico and
  VERSIONINFO into lightcraft.exe (winresource, Windows targets only)
- packaging/linux/ai.storyteller.lightcraft.desktop
- ATTRIBUTION.md entry; icon at the top of README

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

apps/lightcraft/Cargo.toml

@@ -19,6 +19,10 @@ egui = { workspace = true }
 serde_json = { workspace = true }
 log = { workspace = true }
 
+[build-dependencies]
+# Icon + VERSIONINFO for lightcraft.exe; build.rs only uses it when targeting Windows.
+winresource = "0.1"
+
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 rfd = { workspace = true }
 

apps/lightcraft/build.rs

@@ -0,0 +1,28 @@
+//! Windows only: embed the app icon and version info (VERSIONINFO) into `lightcraft.exe`, so
+//! Explorer, the taskbar, the Start menu and Alt-Tab show the lynx.
+//!
+//! On every other target this does nothing. A missing resource compiler is a warning, so a
+//! cross-compile from macOS or Linux still links, unless `LIGHTCRAFT_REQUIRE_WINRES=1` turns it
+//! into an error (for release builds).
+
+fn main() {
+    println!("cargo:rerun-if-changed=build.rs");
+    println!("cargo:rerun-if-changed=../../assets/app-icon/lightcraft.ico");
+    println!("cargo:rerun-if-env-changed=LIGHTCRAFT_REQUIRE_WINRES");
+    if std::env::var("CARGO_CFG_TARGET_OS").as_deref() != Ok("windows") {
+        return;
+    }
+    let mut res = winresource::WindowsResource::new();
+    res.set_icon("../../assets/app-icon/lightcraft.ico")
+        .set("ProductName", "LightCraft")
+        .set("FileDescription", "LightCraft photo library and raw developer")
+        .set("LegalCopyright", "Copyright (c) the LightCraft authors. MIT OR Apache-2.0.")
+        .set("OriginalFilename", "lightcraft.exe")
+        .set("InternalName", "lightcraft");
+    if let Err(e) = res.compile() {
+        if std::env::var_os("LIGHTCRAFT_REQUIRE_WINRES").is_some() {
+            panic!("embedding Windows resources failed: {e}");
+        }
+        println!("cargo:warning=lightcraft.exe built without icon/version resources: {e}");
+    }
+}

apps/lightcraft/src/main.rs

@@ -21,6 +21,19 @@ mod native_menu;
 use lightcraft_engine::Session;
 use lightcraft_ui_egui::{LightcraftApp, Services, UiState};
 
+/// Reverse-DNS app id: Wayland app id, `.desktop` file and hicolor icon name.
+const APP_ID: &str = "ai.storyteller.lightcraft";
+
+/// The window, taskbar and Dock icon (assets/app-icon/, regenerated by packaging/icons.sh). macOS
+/// gets the version with Apple's transparent margin so it sits right among the other Dock icons.
+fn app_icon() -> egui::IconData {
+    #[cfg(target_os = "macos")]
+    let png: &[u8] = include_bytes!("../../../assets/app-icon/lightcraft-macos-512.png");
+    #[cfg(not(target_os = "macos"))]
+    let png: &[u8] = include_bytes!("../../../assets/app-icon/hicolor/256x256/apps/ai.storyteller.lightcraft.png");
+    eframe::icon_data::from_png_bytes(png).unwrap_or_default()
+}
+
 struct App(LightcraftApp, #[cfg(target_os = "macos")] Option<native_menu::NativeMenu>);
 
 impl eframe::App for App {
@@ -251,7 +264,10 @@ fn main() -> eframe::Result {
             .with_drag_and_drop(true)
             .with_fullsize_content_view(true)
             .with_titlebar_shown(false)
-            .with_title_shown(false),
+            .with_title_shown(false)
+            .with_icon(app_icon())
+            // Wayland matches the window to packaging/linux/ai.storyteller.lightcraft.desktop by this id
+            .with_app_id(APP_ID),
         ..Default::default()
     };
     eframe::run_native(