feat(providers): add Venice AI provider

OpenAI-compatible apikey provider (chat/embedding/image) with dynamic
model discovery via modelsFetcher + passthroughModels. No executor needed.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/unit/venice-provider.test.js

@@ -0,0 +1,41 @@
+import { describe, expect, it } from "vitest";
+
+import REGISTRY from "../../open-sse/providers/registry/index.js";
+import { PROVIDERS, PROVIDER_MODELS } from "../../open-sse/providers/index.js";
+
+describe("Venice AI provider", () => {
+  const venice = REGISTRY.find((e) => e.id === "venice");
+
+  it("is registered as an OpenAI-compatible apikey provider", () => {
+    expect(venice).toBeDefined();
+    expect(venice.category).toBe("apikey");
+    expect(venice.transport.baseUrl).toBe("https://api.venice.ai/api/v1/chat/completions");
+    expect(venice.alias).toBe("venice");
+    expect(venice.aliases).toContain("vn");
+  });
+
+  it("enables dynamic model discovery and passthrough", () => {
+    expect(venice.passthroughModels).toBe(true);
+    expect(venice.modelsFetcher).toMatchObject({
+      url: "https://api.venice.ai/api/v1/models",
+      type: "openai",
+    });
+  });
+
+  it("builds into the runtime PROVIDERS map with the openai format default", () => {
+    expect(PROVIDERS.venice).toBeDefined();
+    expect(PROVIDERS.venice.format).toBe("openai");
+    expect(PROVIDERS.venice.baseUrl).toBe("https://api.venice.ai/api/v1/chat/completions");
+  });
+
+  it("exposes its seed models (incl. the signature uncensored model)", () => {
+    const ids = (PROVIDER_MODELS.venice || []).map((m) => m.id);
+    expect(ids.length).toBeGreaterThan(0);
+    expect(ids).toContain("venice-uncensored-1-2");
+  });
+
+  it("keeps every registry id unique after adding venice", () => {
+    const ids = REGISTRY.map((e) => e.id);
+    expect(new Set(ids).size).toBe(ids.length);
+  });
+});