resolveFileServiceForKnowledge was reading os.Getenv("LOCAL_STORAGE_BASE_DIR")
on every request. This causes a mismatch when the variable is not in the
process environment at request time (e.g. it was set programmatically before
app startup but not exported, or the DI-constructed fileService uses a
different configured path).
Fix: store the value in a new localBaseDir field at NewDataAnalysisTool
construction time — the same moment the DI container assembles the local
FileService — and use t.localBaseDir in resolveFileServiceForKnowledge
instead. This guarantees the data-analysis tool always resolves files
under the same base directory that the local FileService was configured
with, eliminating the "path not found" errors when LOCAL storage is used
for a knowledge base while the global storage backend is minio/oss/cos.
Fixes#1040
guangyang1206
d3d433574f