Quiet terminal output by default (opt-in verbose logging)

[dnkats]

Problem

npm start floods the terminal with the main process's per-event log (startup info, focus/blur, memory stats) and Chromium's GPU/init ERROR lines, e.g.:

2026-05-31T15:12:01.387Z: Application starting [Memory: RSS=49MB, Heap=4MB]
...
[34792:...:ERROR:components\viz\service\main\viz_main_impl.cc:189] Exiting GPU process due to errors during initialization
2026-05-31T15:12:02.067Z: Window gained focus [Memory: RSS=90MB, Heap=5MB]

Fix

• log() now only echoes to the terminal when verbose logging is enabled. The full jsmol.log file (in the app's user-data directory) is always written, so troubleshooting info is preserved.
• Chromium's own console output is quieted (--log-level=3, fatal only) unless verbose/--enable-logging is set — this removes the GPU init ERROR noise.
• Verbose logging is opt-in via --verbose/--debug, JLMOL_DEBUG=1, or the new npm run start-verbose script.
• The log-file write is wrapped in try/catch so logging can never break the app.

Note: this is gated by a CLI flag / env var rather than the in-app Settings, because the main-process logging runs at startup before the renderer (where preferences live in localStorage) is available.

Testing

• node --check main.js and package.json JSON both validate.
• npm start should now be quiet; npm run start-verbose restores the detailed terminal log.

🤖 Generated with Claude Code

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