feat(integration): a chat sent to another model starts a new conversation; the server page tests rows, warns while open and confirms a start

[hiyouga]

Summary

Four playground fixes the owner asked for before 0.5.2.

1. Chat: sending to another model starts a new conversation.
   • Before: the backend silently started an empty history whenever the client options changed, while the page kept showing the earlier messages as one continuous chat.
   • Now: sending to another entry (a different model id, client type or base URL) calls /api/clear, starts a new session, and draws a divider: "New conversation with <model> · the messages above are not sent".
   • Composer hint: it says this before Enter is pressed. Picking another model and back before sending changes nothing.
   • Key or extra-header edits: the conversation continues. /api/chat now carries a session's history over when it rebuilds the client, so no history resets silently.
2. Server page: Test / Test all for model rows, sent straight to the upstream through POST /server/api/test.
   • Input: {"model": row}, the row as typed. $VAR cells are read from the playground's environment.
   • Output: "Passed" with first token, total, tokens out (thinking + response) and TPS, or "Failed" with the upstream's message.
   • Limits: three rows at a time, 60 s each.
   • First token: the first event that carries an item. Anthropic reports usage in a stop event at message_start, before any token, so the first event alone would undercount the wait.
3. Open-server banner: while the running server has no keys, the top of the page says anyone who can reach its URL can use the models, with an Add a key button.
4. Start / Apply confirmation:
   • Dialog contents: a native <dialog> showing the listen URL, the model count and the keys the saved file holds, plus the open-server warning when there are none.
   • Keyboard: Enter confirms, Escape cancels, and Ctrl/Cmd+S does nothing while it is open.
   • Why Apply confirms too: it replaces the running server, so it can change the URL or drop the keys.
   • Stop: doesn't ask.

The site docs (server, tracing) and an unreleased changelog entry are included.

Decisions

• Owner: "new conversation", not carrying history across models or keeping a thread per model.
• Owner: the test goes straight to the upstream, not through the running server.
• Earlier messages stay visible above the divider: comparing models on one prompt is what the playground is for.
• Key or extra-header edits continue the conversation: fixing a wrong key mid-chat shouldn't wipe it.

Test plan (vps4)

• Python: 649 passed, 15 skipped. ruff check and ruff format --check clean.
• TS: 637 passed. eslint, tsc --noEmit, prettier and build clean.
• Server page against the stub in headless Chrome: 420 checks, 0 FAIL.
  • Covers the dialog (contents, Escape, focus trap, Enter confirms once), the banner (shows while open, hides after a key is applied) and Test / Test all (disabled until model id + key, Passed / Failed text, a result is dropped when the row is edited).
  • The palette checker's chroma-floor lines on the unchanged neutral greys are not page checks.
• Live, both playgrounds (Python 25761, TS 25762), with real DeepSeek:
  • Server checks: 104 / 103 ok, 0 FAIL.
  • /server/api/test: ok: true with ~300 TPS. An unset $NOPE gives the unset-variable message, sk-bad gives the vendor's 401, and client_type: nope gives the unknown-client message.
  • The banner appears exactly when the console prints Open server:.
• Chat switch check on both playgrounds:
  • Switching the client type posts /api/clear with the old session, draws one divider, and the reply no longer knows the earlier word.
  • A key-only edit keeps the session, and the model still recalls the word from after the switch.

🤖 Generated with Claude Code

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