SCAL-336134: Add developer examples related to chat history for spotter mcp server

[mouryabalabhadra]

Summary

Brings the python-react-agent-simple-ui example up to date with the Spotter 3 MCP toolset, and fixes three things that made it unreliable to run: embed auth, chart rendering after an answer expires, and CSP-blocked iframes.

Changes

Spotter 3 naming

• claude_agent_mcp_server_v2.py → claude_agent_with_spotter3_mcp_server.py
• claude_agent_mcp_server_v2_with_chat_history.py → claude_agent_with_spotter3_mcp_server_and_chat_history.py
• README and env.template re-worded off v1/v2 onto Spotter 3 terms, and the OpenAI / Azure OpenAI (v1) documentation removed.

Embed authentication — fixes the "Duplicate token" alert The client's getAuthToken returned one constant VITE_TS_AUTH_TOKEN. The SDK requires a fresh token per call: once that static token stops verifying, the SDK reports a duplicate token and the callback can never recover, because it hands back the same string.

• New GET /api/ts-token on both servers, minting a short-lived token per request via POST /api/rest/2.0/auth/token/full.

Chart rendering after an answer expires

A ThoughtSpot answer object lives ~8 hours. The chat history stored each answer's iframe_url and answer_id (which is really a {session_id, gen_no} pair), so reopening an older conversation rendered a row of dead embeds.

• The server no longer persists those fields, and strips them on read too, so rows written before this change take the same path.
• GET /api/conversations/{id} now returns each answer's answer_index plus the conversation's analytical_session_id; the client emits a resolver placeholder and the Visual Embed SDK resolves a live URL. Requires the SDK change in PR 2.
• reconcile_answers asks getConversation how many answers each turn actually has, rather than trusting the stored copy. This also recovers answers from turns whose SSE stream was cut off mid-flight: the Agent finishes regardless, so the answer exists on ThoughtSpot's side even when the app recorded none of it.

Raw session updates

TS_MCP_API_VERSION now defaults to latest, and the update readers accept both the server's digested shape and the Agent's raw shape (text-chunk vs text_chunk, metadata.type == "thinking" vs is_thinking, …), so &enable-raw-session-updates=true can be turned on through TS_MCP_URL without a code change. Intermediate "thinking" answers are filtered out — one three-question chat produced eleven answer updates but a single settled one — which also keeps our answer ordering aligned with getConversation's.

System theme

App.css moved fully onto CSS custom properties with a prefers-color-scheme: dark block (no hardcoded colours left bypassing the tokens), and the embed itself gets matching dark customizations variables so the chart doesn't stay white inside a dark page.

Misc

• AnswerFrame removed: answer iframes are injected as markup so React owns only the wrapper and doesn't fight the renderer's replaceWith().
• Dependency bumps: anthropic>=1.2.0,<2, mcp>=2.1.1,<3, httpx → httpx2, FastAPI/uvicorn; @thoughtspot/visual-embed-sdk 1.45.3-mcp.2 → 1.51.1.
• .gitignore: local *.db / -wal / -shm chat-history files.

Testing

• Live chats through both servers: answers stream, embeds render, follow-up turns reuse the same analytical session.
• /api/ts-token verified minting: minted: true, a different token per call, and the minted token authenticates against /callosum/v1/session/isactive.
• /api/conversations list/open/delete exercised against the stored database.
• Client vite build passes.

Notes

server/agent.py (the OpenAI/Azure v1 backend) and the openai entry in requirements.txt are left in place but are no longer documented. Say if they should be removed.