chore: bootstrap kbqa workspace

.env.example

@@ -0,0 +1,21 @@
+KBQA_DASHSCOPE_API_KEY=
+KBQA_DASHSCOPE_BASE_URL=https://dashscope.aliyuncs.com/compatible-mode/v1
+KBQA_CHAT_MODEL=qwen3.5-flash
+KBQA_EMBEDDING_MODEL=text-embedding-v4
+KBQA_EMBEDDING_DIM=1024
+KBQA_DATABASE_URL=sqlite+aiosqlite:///./data/kbqa.sqlite3
+KBQA_MILVUS_URI=./data/milvus/kbqa.db
+KBQA_RAW_DATA_DIR=./data/raw
+KBQA_CHUNK_SIZE=500
+KBQA_CHUNK_OVERLAP=50
+KBQA_RETRIEVAL_TOP_K=5
+KBQA_MAX_RESEARCH_SEARCHES=3
+KBQA_MAX_SOURCES=8
+KBQA_HISTORY_MESSAGE_LIMIT=20
+KBQA_MAX_UPLOAD_MIB=20
+KBQA_CORS_ORIGINS=["http://localhost:5173","http://127.0.0.1:5173"]
+KBQA_RUN_LIVE_TESTS=0
+KBQA_LIVE_TEST_FILE=
+LANGSMITH_TRACING=true
+LANGSMITH_API_KEY=
+LANGSMITH_PROJECT=kbqa-local