[vlad-salone]

Closes #56, the first way out from the issue: the record is truthful about what the encoder did.

With no format, a graphic goes to WebP, and the portable encoder for it only writes lossless. A quality went to it anyway, so the record said quality: 80, lossless: false over the same bytes a run without quality wrote. The facade now treats an explicit quality on a lossless-only encoder it picked per image as it already treated a perceptual target: one encode, Output::target is Resolved::Lossless, Output::lossless is true, no quality in the record. --json, {quality} in a --template, the dry run and the npm package follow from that.

# before: in-80.webp, "quality": 80, "lossless": false
# after:  in-lossless.webp, "lossless": true, no quality
sqzer graphic.png -q 80 --json --template '{stem}-{quality}.{ext}'

Named with Sqzer::format it is a different request: a lossy mode asked for by name. The README and the package README say that throws EncoderUnavailable, and the CLI refuses -f webp -q 80 with exit 3, but the library and the package encoded lossless and reported the quality. They now return EncoderUnavailable with native-webp in available_in, from a new Format::lossy_encoder_features, and Unsupported for PNG, which no build writes lossy, the mirror of what the JPEG encoder says for lossless. One facade test encoded PNG at a quality and now passes Target::Lossless; the changelog entry says the same for a caller who did that.

Not in here: the CLI's render_unavailable still finds the native feature by prefix. It could read lossy_encoder_features instead, but the message is right as it is and that is a separate cleanup.

Checked locally: cargo test -p sqzer-core -p sqzer -p sqzer-cli, cargo clippy --workspace --all-targets --all-features, cargo doc with warnings denied, cargo deny check, and wasm-pack test --node, 17 tests, the new one among them.

🤖 Generated with Claude Code

[greptile-apps]

Confidence Score: 5/5

[Medium impact] The PR appears safe to merge; the previous breaking-change notice is now complete.

Summary

The PR makes reports match lossless-only output and rejects explicitly named lossy modes that the build cannot write.

• Picked WebP graphics report lossless output even with a quality request.
• Named formats reject quality requests their encoders cannot meet.

_{Reviews (2) · Last reviewed commit: "docs(changelog): the named-format refusa..." · Reviewed by Greptile}