Option for unit preference

[yannik131]

Closes #784

[Copilot]

Pull request overview

Adds a new “Preferred unit” annotator setting intended to let users force measurement displays (length/area) to a chosen unit instead of automatic selection.

Changes:

• Adds a Preferred unit selector to the annotator settings UI.
• Centralizes available unit names/multipliers in annotations/utils.js and updates measurement/scale-line rendering to use them.
• Wires the new setting through the settings store and into measurement-related components.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
resources/views/annotations/show/tabs/settings.blade.php	Adds a <select> control for choosing a preferred unit in the settings sidebar.
resources/assets/js/annotations/utils.js	Introduces exported UnitNames/UnitMultipliers; updates ScaleLineProperties to optionally use a fixed unit and formats values via Intl.NumberFormat.
resources/assets/js/annotations/stores/settings.js	Adds a default value for the new unit preference setting.
resources/assets/js/annotations/mixins/measureComponent.vue	Removes local unit arrays (now centralized in utils.js).
resources/assets/js/annotations/components/settingsTab.vue	Provides unit list to the template and persists the selected preferred unit via the settings store.
resources/assets/js/annotations/components/screenshotButton.vue	Passes preferred unit into ScaleLineProperties when drawing the scale line in screenshots.
resources/assets/js/annotations/components/scaleLineIndicator.vue	Passes preferred unit into ScaleLineProperties for the on-canvas scale line indicator.
resources/assets/js/annotations/components/measureTooltip.vue	Uses centralized units, reads preferred unit from settings, and updates formatting/unit selection logic.
resources/assets/js/annotations/annotatorContainer.vue	Adds handling for preferredUnit changes emitted from the settings tab.

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[yannik131]

@mzur The preferred unit can be set using a dropdown in the settings tab, where auto is the default value at the top of the list (previous behaviour). Let me know if you prefer a switch to disable a preferred unit instead, I didn't really know where to put it (maybe to the left of the dropdown, disable/enable the dropdown accordingly?).
To accomodate large/small numbers I switched from the Math.round logic to Intl.NumberFormat("en-US", { maximumSignificantDigits: ... }) which will display leading zeros in small numbers and group digits of larger numbers using commas (388000.02 mm² -> 388,000.02 px²).
Both the scale line and measure tooltips already do a decent job of displaying larger numbers, so I didn't change anything there.