CLI: add a request timeout to download_examples

[simpleqt]

Fixes #2443

Summary

download_examples in src/memos/cli.py fetches the examples zip with requests.get(zip_url) and no timeout. requests waits indefinitely by default, so a stalled connection hangs the CLI forever — no error, no retry, no way out but Ctrl-C.

Fix

Pass an explicit timeout=60 so a stalled download raises requests.RequestException, which the function already catches and reports:

response = requests.get(zip_url, timeout=60)

Regression test

Added tests/test_cli_download_timeout.py:

• red/green verified: the timeout-argument assertion fails against the old implementation and passes with the fix
• also pins that a successful (mocked) download still returns True

ruff check (repo-pinned 0.11.8) passes on both touched files.

AI Disclosure

• Tool(s): Claude (ZCode CLI)
• Used for: debugging assistance, code suggestions, and drafting this PR description. All changes human-reviewed.

[Copilot]

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[Memtensor-AI]

🤖 Open Code Review

Target: PR #2444
Task: 0cd6d31c891e0241
Base: main
Head: sq/cli-download-timeout

🔍 OpenCodeReview found 2 issue(s) in this PR.

---

1. src/memos/cli.py (L48)

Passing a single integer to timeout sets both the connect timeout and the read timeout to 60 s. For a large payload (a full GitHub-archive ZIP that can be tens or hundreds of MB), the read timeout counts from the moment the first byte arrives until the last byte is received — not per-chunk. On a slow or throttled connection this will raise ReadTimeout for a perfectly valid download.

Consider either:

1. A tuple (connect_timeout, read_timeout) with a generous read timeout, e.g. timeout=(10, 300).
2. Streaming the download with stream=True and writing chunks incrementally, which sidesteps the read-timeout issue and avoids buffering the entire ZIP in RAM (response.content).

💡 Suggested Change

Before:

        response = requests.get(zip_url, timeout=60)

After:

        response = requests.get(zip_url, timeout=(10, 300))

---

2. tests/test_cli_download_timeout.py (L44)

Using is True to assert the return value relies on Python's boolean singleton interning. While download_examples does return the literal True, the checklist flags is/is not comparisons against non-singleton literals as a correctness risk. Prefer a plain truthiness check (assert download_examples(...)) or an equality check (assert download_examples(...) == True) to be explicit about intent without depending on identity.

💡 Suggested Change

Before:

        assert download_examples(str(tmp_path)) is True

After:

        assert download_examples(str(tmp_path)) is True  # OK since bool is a singleton, but prefer:
        assert download_examples(str(tmp_path))

Generated by cloud-assistant via Open Code Review.

[Memtensor-AI]

✅ Automated Test Results: PASSED

All tests passed (2/2 executed). memos_python_core/changed-repo-python: 2/2. Duration: 1s [advisory, non-gating] AI-generated tests on branch test/auto-gen-0cd6d31c891e0241-20260930221021: 26/29 passed, 3 failed — these do NOT affect the PR verdict; review the branch manually.

Branch: sq/cli-download-timeout