* Fix: h2non/filetype upgraded to support avif signatures
* Fix: make clean updated to include test/output dirs
* Feature: multi-backend support via IMG_MAP config key as described in #217
* feat: implement both local and remote (proxyMode) mappings for multi-backend
* Feature: multi-backend support via IMG_MAP config key as described in #217
* fix: go-is-svg should be direct import
* fix: imgMap paths are relative to CWD
* feature: IMG_MAP is parsed on start
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Co-authored-by: Nova Kwok <n0vad3v@riseup.net>
