feat(annotations): Enable drawing/region annotations on rotated files

[kduncanhsu]

Summary

• Enables drawing and region annotation creation on rotated documents and images (previously all annotations were disabled on rotation)
• Keeps highlight annotations disabled (highlight annotation button in toolbar is hidden) when rotated (since highlights depend on text selection which doesn't work correctly when rotated yet)
• Removes the PDF-only restriction for the rotate feature, allowing all document types to use rotation when the feature flag is enabled

Changes

• DocBaseViewer: Removed logic that disabled all annotation controls on rotate; now only highlight is gated by rotationAngle === 0. Removed the PDF-only check for enabling the rotate button.
• ImageViewer: Removed logic that disabled annotation controls on rotated images; annotations now remain enabled regardless of rotation.
• Tests: Updated tests to reflect new behavior and removed obsolete test cases.

Test plan

• Verify drawing annotations can be created on a rotated PDF
• Verify region annotations can be created on a rotated PDF
• Verify highlight annotations are hidden when a PDF is rotated
• Verify annotations work on rotated images
• Verify rotate button appears for non-PDF document types when the feature flag is enabled
• Run unit tests (npm test)

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