Coordinate foreground search and background inference CPU budgets

crates/searchi-service/src/pipeline.rs

@@ -258,14 +258,15 @@ impl HybridSearch {
             work.report.chunks + windows.len() <= MAX_SCAN_CHUNKS,
             "Corpus exceeds ANN generation resource budget of {MAX_SCAN_CHUNKS} chunks"
         );
-        for (batch_index, batch) in windows.chunks(MAX_BATCH).enumerate() {
+        let batch_limit = self.embedder.document_batch_limit().clamp(1, MAX_BATCH);
+        for (batch_index, batch) in windows.chunks(batch_limit).enumerate() {
             let texts: Vec<_> = batch.iter().map(|window| window.text.as_str()).collect();
             work.report.document_inference_calls += 1;
             let vectors = self.embedder.embed_documents(&texts, title)?;
             self.store.insert(
                 generation,
                 passage,
-                batch_index * MAX_BATCH,
+                batch_index * batch_limit,
                 batch,
                 &vectors,
             )?;