Subject dimensions are stored repeatedly in classification object

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Package

Choose from the list:

• lib-classifier

Describe the bug

Note that this was first reported in Daily Minor Planet. @lcjohnso Slack thread https://zooniverse.slack.com/archives/C0DTP3L2K/p1709678226020949.

The classifier's SubjectViewerStore records subject dimensions (clientHeight, clientWidth, naturalHeight, naturalWidth) whenever a subject image is loaded. It happens here:

front-end-monorepo/packages/lib-classifier/src/store/SubjectViewerStore/SubjectViewerStore.js

Lines 105 to 116 in d601d3f

	onSubjectReady (event) {
	const { target = {} } = event || {}
	const {
	clientHeight = 0,
	clientWidth = 0,
	naturalHeight = 0,
	naturalWidth = 0
	} = target || {}
	self.dimensions.push({ clientHeight, clientWidth, naturalHeight, naturalWidth })
	self.rotation = 0
	self.loadingState = asyncStates.success
	},

However, since dimensions are pushed into an array, a new record of dimensions is added every time a multi-frame viewer switches frames (flipbook, text + image viewer, multiframe viewer for transcriptions). Because frame is also in the SubjectViewerStore, it updates and triggers a component re-render including a call of onSubjectReady() again and again.

To Reproduce

Steps to reproduce the behavior:

1. Go to a multi-frame subject workflow such as this test transcription project
2. This test flipbook project is also an option Fixed
3. Switch between frames in the viewer
4. Submit a classification
5. Inspect the classification object in the console. You'll see multiple recorded metadata.subject_dimensions like this:

Expected behavior

There should only be one record of dimensions per subject.