workspace: kebab-case crates, app under crates/oak-app, shared versions

All crates take the oak-* kebab-case naming (oak-audio, oak-codec,
oak-common, oak-core, oak-ffmpeg-link, oak-node, oak-otio, oak-plugin,
oak-render, oak-storage, oak-task, oak-timeline, oak-undo), with the
lib identifiers rewritten (oakrender:: -> oak_render::, oakcore_rs:: ->
oak_core::, ...) across all 226 referencing files.

The GUI application moves from the workspace root into
crates/oak-app/: src/, build.rs (paths fixed for the new location) and
tests/ travel with it, the root Cargo.toml becomes workspace-only
([workspace] + workspace.package + profiles), and the app package
inherits the workspace version. The screenshots example becomes a
standalone crate examples/simple_player/ with its own Cargo.toml.

Every crate now inherits the single workspace version
(version.workspace = true), and the workflows' crate paths and the
build docs follow the renames.

Validated with a clean cargo check --workspace.

examples/simple_player/Cargo.toml

@@ -0,0 +1,36 @@
+# Oak Video Editor - Non-Linear Video Editor
+# Copyright (C) 2026 Oak Team
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# A standalone cross-crate integration example: renders the full OakApp
+# shell offscreen and saves screenshots to docs/. Every example under
+# examples/ is its own crate with its own Cargo.toml (see the workspace
+# root manifest), so it can depend on oak-app exactly like an external
+# consumer would.
+
+[package]
+name = "simple_player"
+version = "0.1.0"
+edition = "2021"
+publish = false
+description = "Oak cross-crate integration example: renders the app shell to screenshots"
+
+[dependencies]
+# test-support pulls the visual-test harness (VisualTestAppContext,
+# capture_screenshot) the example drives the shell with.
+gpui = { path = "../../gpui/crates/gpui", features = ["test-support"] }
+gpui_platform = { path = "../../gpui/crates/gpui_platform", features = ["test-support"] }
+oak-app = { path = "../../crates/oak-app" }
+image = "0.25"

examples/simple_player/src/main.rs

@@ -54,17 +54,17 @@ const DEFAULT_WIDTH: f32 = 1600.0;
 #[cfg(target_os = "macos")]
 const DEFAULT_HEIGHT: f32 = 900.0;
 #[cfg(target_os = "macos")]
-const OUT_ZH: &str = concat!(env!("CARGO_MANIFEST_DIR"), "/docs/screenshot-window.png");
+const OUT_ZH: &str = concat!(env!("CARGO_MANIFEST_DIR"), "/../../docs/screenshot-window.png");
 #[cfg(target_os = "macos")]
-const OUT_EN: &str = concat!(env!("CARGO_MANIFEST_DIR"), "/docs/screenshot-window-en.png");
+const OUT_EN: &str = concat!(env!("CARGO_MANIFEST_DIR"), "/../../docs/screenshot-window-en.png");
 #[cfg(target_os = "macos")]
-const OUT_MGR_ZH: &str = concat!(env!("CARGO_MANIFEST_DIR"), "/docs/screenshot-manager.png");
+const OUT_MGR_ZH: &str = concat!(env!("CARGO_MANIFEST_DIR"), "/../../docs/screenshot-manager.png");
 #[cfg(target_os = "macos")]
-const OUT_MGR_EN: &str = concat!(env!("CARGO_MANIFEST_DIR"), "/docs/screenshot-manager-en.png");
+const OUT_MGR_EN: &str = concat!(env!("CARGO_MANIFEST_DIR"), "/../../docs/screenshot-manager-en.png");
 #[cfg(target_os = "macos")]
-const OUT_PREF_ZH: &str = concat!(env!("CARGO_MANIFEST_DIR"), "/docs/screenshot-preferences.png");
+const OUT_PREF_ZH: &str = concat!(env!("CARGO_MANIFEST_DIR"), "/../../docs/screenshot-preferences.png");
 #[cfg(target_os = "macos")]
-const OUT_PREF_EN: &str = concat!(env!("CARGO_MANIFEST_DIR"), "/docs/screenshot-preferences-en.png");
+const OUT_PREF_EN: &str = concat!(env!("CARGO_MANIFEST_DIR"), "/../../docs/screenshot-preferences-en.png");
 
 /// Logical y of the timeline toolbar row, which sits at the top of the
 /// bottom dock panel in the default layout: the dock starts at y 27.5 (the