feat: GPUI desktop port foundation

- scene crate: full project/scene/element model, serde round-trip
  proven against the web SerializedProject shape
- transfer crate: .ocp zip container, cross-compat with web fflate
  archives proven in both directions
- storage crate: filesystem project store replacing IndexedDB,
  .ocp import/export
- media crate: ffmpeg-next 8 decoder (frames, audio, thumbnails,
  waveform summaries)
- playback crate: wall-clock anchored, frame-rounded playback clock
- gpu crate: native texture readback; compositor renders headless
  offscreen on Vulkan (spike test)
- flake devshell: rust toolchain, GPUI native deps, ffmpeg dev,
  bindgen clang args; GPUI hello-world builds
- port plan in notes/gpui-port.md

1 files changed, 56 insertions, 0 deletions

diff --git a/rust/crates/transfer/tests/cross_compat.rs b/rust/crates/transfer/tests/cross_compat.rs
new file mode 100644
index 00000000..02e53ac6
--- /dev/null
+++ b/rust/crates/transfer/tests/cross_compat.rs
@@ -0,0 +1,56 @@
+use transfer::*;
+
+#[test]
+fn parses_web_built_archive() {
+    let archive = std::fs::read(concat!(env!("CARGO_MANIFEST_DIR"), "/tests/fixtures/web-built.ocp"))
+        .expect("web-built fixture");
+    let parsed = parse_project_archive(&archive).expect("parse web archive");
+
+    assert_eq!(
+        parsed
+            .project
+            .get("nested")
+            .and_then(|n| n.get("value"))
+            .and_then(|v| v.as_u64()),
+        Some(42)
+    );
+    assert_eq!(parsed.media.len(), 1);
+    assert_eq!(parsed.media[0].entry, "media/web-asset-web_clip.mov");
+    assert_eq!(parsed.media[0].metadata.media_type, "video");
+    assert_eq!(parsed.media[0].metadata.width, Some(1280.0));
+    assert_eq!(
+        parsed.read_media_data("media/web-asset-web_clip.mov").unwrap(),
+        &[9, 8, 7, 6]
+    );
+}
+
+#[test]
+fn writes_rust_built_archive_for_web_parse() {
+    let archive = build_project_archive(
+        r#"{"version":7,"metadata":{"id":"rust-built"}}"#,
+        vec![ArchiveMediaInput {
+            metadata: ArchivedMediaMetadata {
+                id: "rust-asset".into(),
+                name: "rust audio.mp3".into(),
+                media_type: "audio".into(),
+                file_type: "audio/mpeg".into(),
+                last_modified: 1_753_000_000_000.0,
+                width: None,
+                height: None,
+                duration: Some(1.5),
+                ephemeral: None,
+                thumbnail_url: None,
+            },
+            data: vec![4, 3, 2, 1],
+        }],
+    )
+    .expect("build");
+    let parsed = parse_project_archive(&archive).expect("re-parse");
+    assert_eq!(parsed.media[0].entry, "media/rust-asset-rust_audio.mp3");
+    assert_eq!(
+        parsed
+            .read_media_data("media/rust-asset-rust_audio.mp3")
+            .unwrap(),
+        &[4, 3, 2, 1]
+    );
+}