[DeedleFake]

Why

kawa was a single main package at the repository root, so background scaling, -out parsing, layer surface placement, and text drawing could only be exercised through a running compositor. This moves the compositor into internal/kawa behind a small cmd/kawa and pulls those four pieces into packages that build without cgo and have their own tests. Runtime behavior does not change.

Scope

• cmd/kawa parses the flags, starts the PPROF_ADDR server, calls wlr.InitLog, and runs a kawa.Server.
• internal/kawa is the old main package. Server has exported Terms, OutputConfigs, Background, and BackgroundScale fields and one exported method, Run(ctx), which does not use its context. Release and Shutdown are now release and shutdown.
• internal/bg replaces scaleFunc and parseScale with bg.Scale, which implements encoding.TextMarshaler and TextUnmarshaler for flag.TextVar. The unused scaleTile is gone.
• internal/output replaces OutputConfig, parseOutputConfigs, and parseTransform with output.Config, output.Transform, and output.Parse. kawa maps output.Transform to wlr.OutputTransform with a table.
• internal/anchor replaces placeLayerSurface, placeSpan, and excludeZone with anchor.Place and anchor.Exclude, which take an anchor.State that layers.go builds from the layer surface.
• draw moves to internal/draw, and CreateTextTexture becomes Text, which returns an *image.NRGBA that kawa uploads.
• CI builds ./... and runs go test ./..., plus the extracted packages' tests with CGO_ENABLED=0. The README, launch.sh, and the verify-kawa docs use the new paths.

Existing bugs stay as they are. A small image under -bgscale fit still sits at the corner, a malformed -out entry still panics, and an unknown transform still means normal.

Blast Radius

The install path changes from deedles.dev/kawa to deedles.dev/kawa/cmd/kawa. Nothing outside this module imports the moved code, and the old and new binaries behave the same in every check below.

Verification

• Every commit builds, vets, and passes its tests. go fix -diff reports the same two suggestions as on master.
• A throwaway equivalence test ran verbatim copies of the old functions against the new packages on random inputs. 800,000 background placements, 500,000 -out strings, 1,000,000 layer placements and exclusions, and 6,045 rendered strings all matched. The -out strings that panic before also panic now.
• -h output is byte-identical. stretch, center, fit, and fill parse the same, and ten invalid -bgscale values fail with the same message and exit status 2.
• verify-kawa ran against both builds with the same script. It covered boot and the registry, both menus, New, Tile, Hide, swaybg, waybar's exclusive zone, mako, Xwayland, Log Out, eight -bg and -bgscale combinations plus a missing file, and fifteen -out values. All 39 screenshots are pixel-identical, and the kawa logs match apart from Xwayland event ordering.
• SIGTERM exits with 143 and Log Out exits with 0 in both builds. Backend and socket failures log the same text and exit with 1.