Skip unsupported HEIF/HEIC images during img-dim processing

[si]

Motivation

• Netlify builds were failing with heifsave: Unsupported compression when the imgDim transform attempted to process HEIF/HEIC images.
• The imgDim transform generates blurred placeholders and srcset variants using sharp, which can error on unsupported HEIF compression and abort the build.
• Skipping HEIF/HEIC files during the transform prevents these errors from taking down the entire site build.
• The change is a minimal, low-risk guard that keeps existing processing for supported image types.

Description

• Update _11ty/img-dim.js to normalize dimensions.type with toLowerCase() and detect heif/heic types.
• Early-return from processImage for heif/heic images and emit a console.warn that includes the image src.
• This prevents srcset and blurry-placeholder generation for unsupported HEIF images while leaving other behavior unchanged.
• No other files or transforms were modified.

Testing

• No automated tests were run on this change.

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Codex Task

[netlify]

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[netlify]

❌ Deploy Preview for si-jobling failed. Why did it fail? →

Name	Link
🔨 Latest commit	f43ffcc
🔍 Latest deploy log	https://app.netlify.com/projects/si-jobling/deploys/695905e8b7324a00088f0014