fix(ollama): send chat requests to the /api path

The Ollama SDK appends /chat to the base URL, and Ollama serves chat at
/api/chat. The model list already added the missing /api, so with
"http://localhost:11434" (the address our docs showed) models were listed
but every chat request went to /chat and got a 404. An OpenAI-style
".../v1" address went to /v1/chat.

ollamaApiUrl() turns the server address, ".../v1" and ".../api" into
".../api". Chat, the model list and the settings dialog's request URL
hint all use it. The docs now show http://localhost:11434/api, which also
works on released versions.

tests/unit/ai-providers.test.ts

@@ -434,7 +434,7 @@ describe("Ollama API key security", () => {
 
         expect(createOllamaMock).toHaveBeenCalledWith(
             expect.objectContaining({
-                baseURL: "https://my-ollama.com",
+                baseURL: "https://my-ollama.com/api",
                 headers: { Authorization: "Bearer client-key" },
             }),
         )
@@ -448,7 +448,7 @@ describe("Ollama API key security", () => {
 
         expect(createOllamaMock).toHaveBeenCalledWith(
             expect.objectContaining({
-                baseURL: "https://cloud.ollama.com",
+                baseURL: "https://cloud.ollama.com/api",
                 headers: { Authorization: "Bearer server-key" },
             }),
         )
@@ -483,7 +483,24 @@ describe("Ollama API key security", () => {
 
         expect(createOllamaMock).toHaveBeenCalledTimes(1)
         const callArgs = createOllamaMock.mock.calls[0][0]
-        expect(callArgs.baseURL).toBe("https://my-ollama.com")
+        expect(callArgs.baseURL).toBe("https://my-ollama.com/api")
         expect(callArgs).not.toHaveProperty("headers")
     })
+
+    it("sends chat to Ollama's /api for a server address or a /v1 URL", () => {
+        delete process.env.OLLAMA_API_KEY
+
+        for (const baseUrl of [
+            "http://localhost:11434",
+            "http://localhost:11434/",
+            "http://localhost:11434/v1",
+            "http://localhost:11434/api",
+        ]) {
+            createOllamaMock.mockClear()
+            getAIModel({ provider: "ollama", baseUrl, modelId: "llama3.2" })
+            expect(createOllamaMock.mock.calls[0][0].baseURL).toBe(
+                "http://localhost:11434/api",
+            )
+        }
+    })
 })