feat: add relation notes

[joshpi-1345]

Summary

• add a relation note field in the details panel
• serialize and deserialize relation notes with annotation results
• add store and relations panel tests for note persistence and editing

Closes #5495

Tests

• ./node_modules/.bin/biome check libs/editor/src/common/TextArea/TextArea.tsx libs/editor/src/components/SidePanels/DetailsPanel/Relations.prefix.css libs/editor/src/components/SidePanels/DetailsPanel/Relations.tsx libs/editor/src/components/SidePanels/DetailsPanel/tests/Relations.test.tsx libs/editor/src/stores/Annotation/Annotation.js libs/editor/src/stores/RelationStore.js libs/editor/src/stores/tests/RelationStore.test.js
• ./node_modules/.bin/jest --config=libs/editor/jest.config.js --runInBand --runTestsByPath libs/editor/src/stores/tests/RelationStore.test.js libs/editor/src/components/SidePanels/DetailsPanel/tests/Relations.test.tsx
• corepack yarn nx run editor:unit

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