feat: scaffold CLI and minimal issue list (task 0001)

Tracer bullet for gitea-axi: runnable npm package on axi-sdk-js with
gitea-js as the sole HTTP layer, ESM on Node 20+.

- issue list with --state/--limit, default fields, count line from
  X-Total-Count, type=issues guard, explicit empty state, and next-step
  suggestions
- repo context detection from the git origin remote (SSH/scp/HTTPS),
  tea credential discovery with the three-way login-matching split, and
  -R/--repo and --login overrides (flag > env > auto)
- token retrieval via tea login helper get: tea's login list JSON
  carries no token (ADR 0001 amended)
- full AxiError classification table with path-based 404 split, TOON
  errors on stdout, exit codes 0/1/2
- test mode (GITEA_AXI_API_URL/TOKEN/REPO) suppressing subprocesses,
  fixture server, and vitest suites driving the CLI seam (50 tests)

test/context.test.ts

@@ -0,0 +1,119 @@
+import { afterEach, describe, expect, it } from "vitest";
+import { startFixtureServer, type FixtureServer } from "./fixture-server.js";
+import { runCliTest, testModeEnv } from "./harness.js";
+
+let server: FixtureServer | undefined;
+
+afterEach(async () => {
+  await server?.close();
+  server = undefined;
+});
+
+describe("context overrides", () => {
+  it("prefers the -R flag over GITEA_AXI_REPO", async () => {
+    server = await startFixtureServer([
+      { method: "GET", path: "/api/v1/repos/flagowner/flagrepo/issues", body: [] },
+    ]);
+    const { exitCode } = await runCliTest(
+      ["issue", "list", "-R", "flagowner/flagrepo"],
+      { env: testModeEnv(server.url) },
+    );
+
+    expect(exitCode).toBe(0);
+    expect(server.requests[0]!.path).toBe("/api/v1/repos/flagowner/flagrepo/issues");
+  });
+
+  it("accepts -R before the command", async () => {
+    server = await startFixtureServer([
+      { method: "GET", path: "/api/v1/repos/flagowner/flagrepo/issues", body: [] },
+    ]);
+    const { exitCode } = await runCliTest(
+      ["-R", "flagowner/flagrepo", "issue", "list"],
+      { env: testModeEnv(server.url) },
+    );
+
+    expect(exitCode).toBe(0);
+    expect(server.requests[0]!.path).toBe("/api/v1/repos/flagowner/flagrepo/issues");
+  });
+
+  it("accepts the --repo=OWNER/NAME form", async () => {
+    server = await startFixtureServer([
+      { method: "GET", path: "/api/v1/repos/flagowner/flagrepo/issues", body: [] },
+    ]);
+    const { exitCode } = await runCliTest(
+      ["issue", "list", "--repo=flagowner/flagrepo"],
+      { env: testModeEnv(server.url) },
+    );
+
+    expect(exitCode).toBe(0);
+    expect(server.requests[0]!.path).toBe("/api/v1/repos/flagowner/flagrepo/issues");
+  });
+
+  it("includes the -R override in next-step suggestions when context came from a flag", async () => {
+    server = await startFixtureServer([
+      { method: "GET", path: "/api/v1/repos/flagowner/flagrepo/issues", body: [] },
+    ]);
+    const { stdout } = await runCliTest(
+      ["issue", "list", "-R", "flagowner/flagrepo"],
+      { env: testModeEnv(server.url) },
+    );
+
+    expect(stdout).toContain("-R flagowner/flagrepo");
+  });
+
+  it("includes the -R override in suggestions when context came from the environment", async () => {
+    server = await startFixtureServer([
+      { method: "GET", path: "/api/v1/repos/testowner/testrepo/issues", body: [] },
+    ]);
+    const { stdout } = await runCliTest(["issue", "list"], {
+      env: testModeEnv(server.url),
+    });
+
+    expect(stdout).toContain("-R testowner/testrepo");
+  });
+
+  it("fails with REPO_NOT_FOUND when test mode has no repository context", async () => {
+    server = await startFixtureServer([]);
+    const { stdout, exitCode } = await runCliTest(["issue", "list"], {
+      env: { GITEA_AXI_API_URL: server.url, GITEA_AXI_TOKEN: "test-token" },
+    });
+
+    expect(exitCode).toBe(1);
+    expect(stdout).toContain("code: REPO_NOT_FOUND");
+    expect(stdout).toContain("GITEA_AXI_REPO");
+  });
+
+  it("rejects a malformed -R value with exit code 2", async () => {
+    server = await startFixtureServer([]);
+    const { stdout, exitCode } = await runCliTest(
+      ["issue", "list", "-R", "not-a-repo"],
+      { env: testModeEnv(server.url) },
+    );
+
+    expect(exitCode).toBe(2);
+    expect(stdout).toContain("code: VALIDATION_ERROR");
+    expect(stdout).toContain("OWNER/NAME");
+  });
+
+  it("rejects -R without a value with exit code 2", async () => {
+    const { stdout, exitCode } = await runCliTest(["issue", "list", "-R"], {
+      env: { GITEA_AXI_API_URL: "http://127.0.0.1:1" },
+    });
+
+    expect(exitCode).toBe(2);
+    expect(stdout).toContain("code: VALIDATION_ERROR");
+  });
+
+  it("test mode never spawns git or tea", async () => {
+    // An empty PATH makes any subprocess spawn fail loudly; success here
+    // proves the git and tea subprocesses were suppressed.
+    server = await startFixtureServer([
+      { method: "GET", path: "/api/v1/repos/testowner/testrepo/issues", body: [] },
+    ]);
+    const { exitCode } = await runCliTest(["issue", "list"], {
+      env: { ...testModeEnv(server.url), PATH: "" },
+    });
+
+    expect(exitCode).toBe(0);
+  });
+});