fix: set COCOINDEX_SOURCE_MAX_INFLIGHT_ROWS=256 to prevent "too many open files" error (#300)

Fixes #293. Users experienced "Too many open files (os error 24)" during
indexing because CocoIndex's default concurrency (1024 inflight rows) opens
more file handles than OS limits allow (typically 256-1024).

Set COCOINDEX_SOURCE_MAX_INFLIGHT_ROWS=256 in both code paths that invoke
cocoindex (pipeline.run_cocoindex_update and server._cocoindex_subprocess_env).

Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>

Author: HumanBean17

java_codebase_rag/pipeline.py

@@ -128,6 +128,10 @@ def run_cocoindex_update(
             stdout="",
             stderr=f"java_index_flow_lancedb.py not found under {bd}",
         )
+    # Set CocoIndex concurrency limits to prevent "too many open files" error
+    # See: https://github.com/HumanBean17/java-codebase-rag/issues/293
+    env = env.copy()
+    env.setdefault("COCOINDEX_SOURCE_MAX_INFLIGHT_ROWS", "256")
     cmd: list[str] = [str(exe), "update", COCOINDEX_TARGET]
     if full_reprocess:
         cmd.extend(["--full-reprocess", "-f"])

server.py

@@ -162,6 +162,9 @@ def _cocoindex_subprocess_env(project_root: Path) -> dict[str, str]:
     idx = os.environ.get("JAVA_CODEBASE_RAG_INDEX_DIR", "").strip()
     if idx:
         sub_env["JAVA_CODEBASE_RAG_INDEX_DIR"] = str(Path(idx).expanduser().resolve())
+    # Set CocoIndex concurrency limits to prevent "too many open files" error
+    # See: https://github.com/HumanBean17/java-codebase-rag/issues/293
+    sub_env.setdefault("COCOINDEX_SOURCE_MAX_INFLIGHT_ROWS", "256")
     return sub_env