feat(annotations): correct drawing coords on rotated pages

[kduncanhsu]

Summary

Adds support for live annotation drawing on rotated pages/images. This is in preparation for enabling annotation creation on rotated PDFs and images, where the annotation controls were previously hidden. Without this change, simply re-enabling annotation creation controls in the rotated state would cause the live drawing input to be offset from the user’s cursor.

This PR:

• Applies inverse rotation to convert screen-space mouse coordinates into the annotation layer's local coordinate system
• Uses offsetWidth/offsetHeight (pre-transform dimensions) for percentage instead of getBoundingClientRect() which returns post-transform AABB dimensions
• Removes the isRotated guard that blocked region annotation creation on rotated files

For further clarity, here is the live pointer capture flow when drawing annotations:

1. Mouse events provide clientX/clientY coordinates in screen space.
2. getPosition applies the inverse rotation transform to convert screen-space coordinates into the annotation layer’s local pre-transform coordinate space (in pixels).
3. getPoints/getShape normalize those local-space pixel coordinates into percentages using the annotation layer’s pre-transform offsetWidth/offsetHeight.”

Test plan

• Rotate a PDF 90°, 180°, 270° counterclockwise and verify drawing annotations follow the cursor
• Rotate an image 90°, 180°, 270° and verify region annotations follow the cursor
• Verify annotations on unrotated (0°) files still work correctly
• Verify stored annotations remain anchored to content when rotation changes

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