Add DeepSeek V4 Flash and Pro models

[avaritiachaos]

Summary

• add DeepSeek V4 Flash and Pro model definitions
• support DeepSeek V4 thinking mode controls and reasoning_effort mapping (xhigh -> max)
• cover native DeepSeek and OpenAI-compatible DeepSeek endpoints with tests

Test plan

• corepack pnpm --dir src exec vitest run api/providers/tests/deepseek.spec.ts api/providers/tests/openai.spec.ts
• corepack pnpm --dir src exec tsc --noEmit
• corepack pnpm --dir packages/types exec tsc --noEmit

Interactively review PR in Roo Code Cloud

[466348376]

太好了。太好了，坐着等两三天了

[466348376]

懂github的朋友，如果更新了deepseek v4后，麻烦艾特我一下，谢谢

[lazyupdate]

Thanks for this PR — the thinking mode and reasoning_effort mapping work is solid.

However, there's a bug in the streaming handler that this doesn't address:

src/api/providers/openai.ts line ~234:

if ("reasoning_content" in delta && delta.reasoning_content) {

When DeepSeek V4 returns an empty reasoning_content: "" (which it does in certain streaming chunks), delta.reasoning_content is falsy → the block is skipped → reasoning_content is never stored on the assistant message → the next request lacks it → DeepSeek returns 400.

Fix (1 line):

- if ("reasoning_content" in delta && delta.reasoning_content) {
+ if ("reasoning_content" in delta && typeof delta.reasoning_content === "string") {

To reproduce in isolation:

1. Run a mock OpenAI server that SSE-streams reasoning_content: "" + a tool_call (e.g. bash)
2. Let the agent execute the tool and construct the follow-up request
3. The mock returns 400 because reasoning_content was dropped
4. With the typeof fix, the field is preserved (even as "") and the mock returns 200

[avaritiachaos]

@lazyupdate

Thanks for catching this edge case and providing the detailed reproduction steps!

I've applied the typeof fix to preserve the empty reasoning chunks. I also checked the official deepseek.ts provider, fixed the exact same falsy evaluation issue there, and added regression tests for both.

PTAL!