Nomad changes

docs/snippets/rust/plugins/embedding_backend.md

@@ -0,0 +1,47 @@
+```rust title="Rust"
+use kreuzberg::plugins::{EmbeddingBackend, Plugin, register_embedding_backend};
+use kreuzberg::{EmbeddingConfig, EmbeddingModelType, Result, embed_texts};
+use async_trait::async_trait;
+use std::sync::Arc;
+
+// Wrap an already-loaded embedder (e.g. a tuned ONNX session or any host-language
+// embedder) so kreuzberg can call back into it during chunking and standalone
+// embed requests.
+struct MyEmbedder {
+    // Hold whatever model handles the host already owns.
+}
+
+impl Plugin for MyEmbedder {
+    fn name(&self) -> &str { "my-embedder" }
+    fn version(&self) -> String { "1.0.0".to_string() }
+    fn initialize(&self) -> Result<()> { Ok(()) }
+    fn shutdown(&self) -> Result<()> { Ok(()) }
+}
+
+#[async_trait]
+impl EmbeddingBackend for MyEmbedder {
+    // Captured once at registration; used for shape validation on every dispatch.
+    fn dimensions(&self) -> usize { 768 }
+
+    async fn embed(&self, texts: Vec<String>) -> Result<Vec<Vec<f32>>> {
+        // Delegate to the already-loaded host model.
+        Ok(texts.iter().map(|_| vec![0.0; 768]).collect())
+    }
+}
+
+fn main() -> Result<()> {
+    // Register once at startup.
+    register_embedding_backend(Arc::new(MyEmbedder {}))?;
+
+    let config = EmbeddingConfig {
+        model: EmbeddingModelType::Plugin { name: "my-embedder".to_string() },
+        // Optional: bound the wait on a hung backend (default 60s; `None` disables).
+        max_embed_duration_secs: Some(30),
+        ..Default::default()
+    };
+
+    let vectors = embed_texts(&["Hello, world!", "Second text"], &config)?;
+    assert_eq!(vectors.len(), 2);
+    Ok(())
+}
+```