fix(context): tolerate a trailing /api/v1 in the base URL

The client (gitea-js) appends /api/v1 to the base URL itself, so a
GITEA_AXI_API_URL that already carries it — a natural guess given the
variable's name — doubled the segment and failed as a spurious
REPO_NOT_FOUND. Normalize the base URL by stripping a trailing /api/v1
(and any trailing slashes) on both the env-URL and tea-login paths, so the
host base and the /api/v1 endpoint both resolve.

test/context.test.ts

@@ -1,4 +1,6 @@
 import { afterEach, describe, expect, it } from "vitest";
+import { resolveRepoContext } from "../src/context.js";
+import type { CliDeps } from "../src/deps.js";
 import { startFixtureServer, type FixtureServer } from "./fixture-server.js";
 import { runCliTest, testModeEnv } from "./harness.js";
 
@@ -117,3 +119,49 @@ describe("context overrides", () => {
     expect(exitCode).toBe(0);
   });
 });
+
+describe("apiUrl normalization", () => {
+  function depsWithApiUrl(apiUrl: string): CliDeps {
+    return {
+      env: {
+        GITEA_AXI_API_URL: apiUrl,
+        GITEA_AXI_REPO: "acme/widgets",
+        GITEA_AXI_TOKEN: "test-token",
+      },
+      cwd: process.cwd(),
+      globals: {},
+    };
+  }
+
+  it("strips a trailing /api/v1 suffix from the host base", async () => {
+    const context = await resolveRepoContext(
+      depsWithApiUrl("https://git.example.com/api/v1"),
+    );
+
+    expect(context.apiUrl).toBe("https://git.example.com");
+  });
+
+  it("strips a trailing /api/v1/ with a trailing slash", async () => {
+    const context = await resolveRepoContext(
+      depsWithApiUrl("https://git.example.com/api/v1/"),
+    );
+
+    expect(context.apiUrl).toBe("https://git.example.com");
+  });
+
+  it("leaves a host base without an /api/v1 suffix unchanged", async () => {
+    const context = await resolveRepoContext(
+      depsWithApiUrl("https://git.example.com"),
+    );
+
+    expect(context.apiUrl).toBe("https://git.example.com");
+  });
+
+  it("strips a lone trailing slash from the host base", async () => {
+    const context = await resolveRepoContext(
+      depsWithApiUrl("https://git.example.com/"),
+    );
+
+    expect(context.apiUrl).toBe("https://git.example.com");
+  });
+});