fix(cli): preserve detect_runtime_binary --version output on cp1252 Windows consoles

[4gjnbzb4zf-sudo]

{"schema":"spark-compete-hotfix-v1","team":{"name":"SparkThisUp","contact_handle":"@ValhallaBuilder","device_holder_github":"4gjnbzb4zf-sudo"},"target_repo":{"id":"vibeforge1111/spark-cli","branch":"master"},"finding":{"title":"detect_runtime_binary drops node/python/npm --version output as UnicodeDecodeError on Windows cp1252 consoles","summary":"detect_runtime_binary runs ' --version' with subprocess.run(text=True) and timeout=5, but never sets encoding. It already catches OSError and TimeoutExpired into a structured failure dict; UnicodeDecodeError is NOT caught. On Windows VPS hosts with cp1252/cp936 consoles, several runtime binaries emit non-ASCII bytes in their --version banner: 'uv 0.x.x (...) Copyright (c) ...' includes an em-dash on some versions, npm has translated banners with LANG, and Node's --no-warnings notice can carry locale-translated text when shimmed. When subprocess.run decodes with the platform default, UnicodeDecodeError escapes the OSError-only except block and aborts 'spark doctor', 'spark verify --onboarding', and 'spark autostart status' with a raw traceback — the exact diagnostic surfaces the operator needs to recover.","severity":"medium","category":"reliability","owner_surface":["spark-cli"],"reproduction":{"steps":["1. Windows VPS, chcp 1252, LANG=de_DE or zh_CN.","2. Install uv with a --version banner containing the em-dash (or use a shim that wraps node with a translated banner).","3. Run 'spark doctor' — detect_runtime_binary('uv') / ('npm') / ('node') is called in the runtime probe.","4. UnicodeDecodeError replaces the structured {present, path, version, error} dict and aborts the doctor flow."],"evidence_types":["redacted_terminal_excerpt"],"redacted_terminal_excerpt":"UnicodeDecodeError: 'charmap' codec can't decode byte 0x96 in position 12"},"proposed_fix":{"strategy":"Add encoding='utf-8', errors='replace' to the subprocess.run that probes ' --version'. Two-line additive change. Matches the recipe sister fix #872 used for run_git_or_exit, #884 used for run_autostart_helper, #886 used for write_windows_startup_script, and our PRs #888/#890/#891/#892 used across the module install+update chain.","files_expected":["src/spark_cli/cli.py"],"diff_size_estimate_lines":2},"material_new_value":"Closes the doctor / verify / autostart Windows-cp1252 crash window for runtime-binary version probes — a distinct surface from the install/update chain. R24 batch has accepted multiple sibling encoding fixes. Dedup vs #872 (run_git_or_exit, git only), #884 (autostart helper), #886 (PowerShell startup writer), and our open PRs (#888/#890/#891/#892, all module install+update git): detect_runtime_binary is a separate diagnostic call site driving 'spark doctor', not git.","honest_severity_basis":"Medium because doctor is the operator's first recovery surface when something is wrong; a crash inside the runtime-probe loop forces operators to debug Python tracebacks instead of getting the shaped {present, path, version} report.","confidence_score":0.9}}

[4gjnbzb4zf-sudo]

TL;DR — detect_runtime_binary runs <binary> --version with text=True and no encoding. It catches OSError and TimeoutExpired into a structured dict, but UnicodeDecodeError is uncaught. On Windows cp1252 / translated locales, uv and npm --version banners can emit non-ASCII bytes (em-dash, locale-translated lines), and spark doctor / spark verify --onboarding / spark autostart status crash with a raw traceback instead of returning {present, path, version, error}. Fix: add encoding="utf-8", errors="replace" — same recipe as sister #872 (git), #884 (autostart helper console), and our PRs #888/#890/#891/#892. Distinct surface — diagnostic, not git.