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, 35 insertions, 0 deletions

diff --git a/rust/crates/effect-defs/src/registry.rs b/rust/crates/effect-defs/src/registry.rs
new file mode 100644
index 00000000..340f9b9b
--- /dev/null
+++ b/rust/crates/effect-defs/src/registry.rs
@@ -0,0 +1,35 @@
+use std::collections::HashMap;
+
+use crate::{EffectDefsError, types::EffectDefinition};
+
+#[derive(Default)]
+pub struct EffectsRegistry {
+    definitions: HashMap<String, EffectDefinition>,
+}
+
+impl EffectsRegistry {
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    pub fn register(&mut self, definition: EffectDefinition) {
+        self.definitions
+            .insert(definition.effect_type.to_string(), definition);
+    }
+
+    pub fn has(&self, key: &str) -> bool {
+        self.definitions.contains_key(key)
+    }
+
+    pub fn get(&self, key: &str) -> Result<&EffectDefinition, EffectDefsError> {
+        self.definitions
+            .get(key)
+            .ok_or_else(|| EffectDefsError::UnknownEffect {
+                effect_type: key.to_string(),
+            })
+    }
+
+    pub fn get_all(&self) -> Vec<&EffectDefinition> {
+        self.definitions.values().collect()
+    }
+}