Enhance Foresight AI demo replay and evidence citations

[liyizhouAI]

Summary

• add a stable Ningbo Bank cached demo path with replay/report/history support for live presentation
• expand the interactive report to roughly 10k Chinese characters, including 30 direct Agent answer snippets for evidence-rich Report Agent responses
• add Report Agent citations and clickable evidence chips in Step 5 so Sxx/Axx markers jump back to the relevant report section
• improve graph/report/demo deployment support and production API routing for foresight.yizhou.chat

Verification

• backend py_compile: app/services/cached_replays.py, app/api/report.py, app/utils/llm_client.py
• frontend npm run build
• live API: /health returns 200
• live report: report_nb_hnw_ai_case markdown length 9985 chars; Agent evidence section length 5403 chars
• live chat: /api/report/chat returns success=true, llm_used=true, model_used=glm-4-flash, citations present
• browser QA: Step 5 renders citation chips; clicking A01 scrolls/highlights section 02

Deployment

• deployed current build to Tencent Cloud frontend and backend
• verified https://foresight.yizhou.chat/interaction/report_nb_hnw_ai_case after deployment