add SI unit toggle button

[otomn]

closes #77

[Copilot]

Pull request overview

Adds a UI toggle to switch between IEC (KiB = 1024) and SI (KB = 1000) byte units, addressing the requested disambiguation in #77.

Changes:

• Add unitIsSI state to PluginManager and use it in format(bytes) to choose 1000 vs 1024 and unit labels (KB vs KiB, etc.).
• Add a new “KiB/KB” toggle button to the header UI.
• Add toggleUnit() and (currently) auto-toggle on macOS during startup.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 4 comments.

File	Description
app/js/utils.js	Makes byte formatting depend on a new SI/IEC toggle and changes unit labels accordingly.
app/js/router.js	Introduces PluginManager.unitIsSI state.
app/js/radar.js	Adds unit toggle behavior (including a macOS startup toggle) and reloads last data on toggle.
app/index.html	Adds the unit toggle button to the toolbar.

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[Copilot]

toggleUnit() always calls PluginManager.loadLast(), which will throw if LASTLOAD_FILE does not exist yet (e.g., before the first scan, or if the file was deleted). Guard the reload (similar to colors.js, which checks PluginManager.data) and update the UI without forcing a reload when there’s no data to reload.

Suggested change

	unit_button.textContent = PluginManager.unitIsSI ? "KB" : "KiB"
	PluginManager.loadLast()
	unit_button.textContent = PluginManager.unitIsSI ? "KB" : "KiB";
	if (PluginManager.data) {
	PluginManager.loadLast();
	}

[Copilot]

The PR introduces platform-specific behavior (auto-switching units on macOS) that isn’t described in the PR title/description or the linked issue. If the intent is to only add a user-controlled toggle, consider removing the macOS default-switch or documenting/justifying it and persisting the preference so it’s consistent across restarts.

[Copilot]

format() now directly reads global.PluginManager.unitIsSI, which will throw if PluginManager is not initialized yet (or if this module is used in the non-renderer Node context). Make this access defensive (e.g., default to binary units when PluginManager/unitIsSI is missing) so format() remains safe to call in all existing environments.

Suggested change

	let unitIsSI = global.PluginManager.unitIsSI
	let unitIsSI = !!(global && global.PluginManager && global.PluginManager.unitIsSI);

[Copilot]

Calling toggleUnit() during ready() on macOS can crash on a fresh run because toggleUnit() triggers PluginManager.loadLast(), which reads LASTLOAD_FILE unconditionally. Either remove the automatic toggle, or ensure toggleUnit() only reloads data when a previous snapshot exists (and/or when PluginManager.data is set).

Suggested change

	if (navigator.platform.includes("Mac")) {
	toggleUnit()
	}