⚡ Bolt: [performance] Concurrent tool execution and multi-repo search in retrieval pipelines

[ishaanxgupta]

💡 What: Refactored LLM tool execution loops in RetrievalPipeline and CodeRetrievalPipeline to run independently spawned tool calls concurrently using asyncio.gather. Also applied concurrent searching across multiple repositories in _search_symbols and _search_files.
🎯 Why: Sequential tool execution caused significant compounding latency for complex questions where the LLM needs data from multiple domains (e.g. search_profile and search_temporal simultaneously) or when querying the default all-repository context. This bottleneck forced O(N) network latency for parallelizable tasks.
📊 Impact: Shifts I/O-bound retrieval from sequential to parallel latency. Expected to reduce end-to-end multi-domain retrieval time by >50% depending on the number of concurrent tool calls and repositories.
🔬 Measurement: View tracing output showing tool execution durations converging towards the slowest individual query, eliminating sequential delay accumulation. Evaluated syntactically with ast.parse and statically reviewed for functional correctness to avoid race conditions when appending to shared lists like sources.

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PR created automatically by Jules for task 963796135469649119 started by @ishaanxgupta

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