* Add the rank-0 Item leaf variants to the Graphic enum, rendering leaves and list rows through shared per-row logic
* Traverse the rank-0 Graphic leaf variants in the vector node helpers and flattening
* Reach rank-0 vector graphics from the styling and gradient-fitting helpers
* Two code review fixes
* Fix comment
* Make the Artboard and Gradient newtype fields public to match the other list newtypes
* Rename the Graphic enum's self-named Graphic::Graphic variant to Graphic::GraphicList
* Rename the Graphic::Vector variant to Graphic::VectorList
* Rename the Graphic::RasterCPU variant to Graphic::RasterCPUList
* Rename the Graphic::RasterGPU variant to Graphic::RasterGPUList
* Rename the Graphic::Color variant to Graphic::ColorList
* Rename the Graphic::Gradient variant to Graphic::GradientList
* Rename the Graphic::Text variant to Graphic::TextList
* Restore the SVG group tag comment that the variant rename sweep clobbered
* Add the appearance model types and attribute constants
* Dual-write the appearance attribute alongside the fill/stroke pair in all paint-writing nodes
* Read paint from the appearance attribute in the renderer, analysis, metadata, and editor, cascading from ancestors
* Retire the fill/stroke attribute pair and the Vector stroke field in favor of the appearance attribute
* Replace the Stroke node's paint order input with the relative chain order of the Fill and Stroke nodes
* Code review fixes
* Re-save demo art
* Stamp coverages in place and fuse the renderer's per-item appearance reads into single walks
* Treat an empty appearance as the undeclared state so padded rows inherit instead of blocking the cascade
* Update demo art
* Treat padded appearance rows as undeclared in the boolean flatten's group recursion
* Honor clipping masks when rendering Vector[] lists, not just Graphic[] groups
* Keep per-layer click targets when a Vector[] round-trips through a Graphic[] wrapper
* Skip the rebuild and the merged-layers snapshot when flattening a lone anonymous graphic wrapper
* Fix a group's bounds excluding its raster children and stretching to the origin
* Fix SVG clipping masks landing in the wrong space when sibling layers differ in transform
* New nodes: 'Gradient Reverse', 'Gradient Shift', and 'Gradient Stretch' nodes for rearranging a ramp's stops
* Clip a lone out-of-range stop into the bake, and correct the docs that still promised edge-held stops
* Upgrade Vello to a git main revision that honors the brush's interpolation alpha space
* Interpolate Vello gradients with straight alpha, matching the SVG renderer
* Draw the gradient picker strip and fill swatches as SVG so transparency previews with straight alpha
* Keep gradient stop handles opaque so a transparent stop's RGB stays visible
* Paint a stopless gradient's picker strip and swatch black rather than transparent
* Delete dead code function
* Add a Gradient Interpolation axis with Stepped, Linear, and Smooth paths through the stops
* Keep the gradient interpolation attached when dragging stops in the picker
* Give the gradient popover's dropdowns the same tooltips as their row labels
* Order the gradient popover with Intrp. above Space
* Hold gradient stops in place when the cyclic flag is toggled
* Fix wrong Smooth gradient colors around stops sitting on the ramp boundaries
* Consolidate gradient settings plumbing and fix bugs
* Bundle whole-ramp gradient settings into GradientSettings across the editor plumbing
* Name the Smooth gradient interpolation's spline type in its tooltip
* Linearize the gamma hex stop colors recovered from imported Graphite SVGs
* Code review
* Aim the Smooth bake's seam subdivision at the copied boundary color
* Add GradientEvaluator to build gradient sampling state once per loop instead of per sample
* Correct the gradient evaluator's documented setup cost to O(n log n)
* Add a Cyclic gradient attribute that wraps the stop list through the 1|0 boundary back to the first stop
* Show the wrap segment's midpoint diamond in the color picker spectrum strip when cyclic
* Keep the wrap midpoint diamond tracking the pointer by a wrapped strip width when dragged past the ends
* Give the Gradient tool's viewport overlay the same cyclic wrap midpoint diamond and drag behavior
* Correct the docs claiming the final stop's midpoint is always ignored now that cyclic uses it
* Move the gradient cyclic toggle onto the Ends row as a Link icon checkbox
* Update labels
* Register GradientHueDirection with the Data panel so its attribute column renders
* Reword wrap segment to wrapped interval and stray segment usages to interval
* Clean up comments
* Fix the color picker write-back losing default position elision and the blend path guessing the cyclic flag
* Add an OkLab gradient interpolation space and make it the new default
* Fix the Properties panel fill row resetting the gradient interpolation space to the default
* Add OkLch, Lab, LCh, and HSL gradient interpolation spaces
* Add a hue direction attribute and picker choice for polar gradient interpolation spaces
* Add an HSV gradient interpolation space
* Rename the sRGB Linear and sRGB Gamma gradient spaces to RGB Linear and RGB Gamma
* Divide the gradient interpolation dropdown between absolute and relative color spaces
* Rename the OkLch gradient interpolation space to OkLCh for channel-notation capitalization
* Shorten the color picker popover's hue direction row label to Arc
* Call the Gradient Interpolation node's parameter Space and extend the picker tooltip title to match
* Rename the gradient interpolation attribute and type family to gradient space
* Rename the gradient tool's gradient space transform to gradient to viewport transform
* Add serde aliases and a node replacement covering the gradient space renames
* Give the gradient space choices artist-facing labels and reorder the dropdown sections
* Add a Gradient Hue Direction node and its attribute read node
* Say interpolate instead of blend for gradient stop color traversal in docs and tooltips
* Label the polar perceptual gradient spaces as Perceptual Hue and group the dropdown sections by geometry
* Add a migration alias covering the gradient space attribute reader rename
* Carry the gradient hue direction attribute through boolean operations
* Register GradientHueDirection wire types in the node registry
* Build dropdown menu entries from choice type metadata
* Add a gradient interpolation color space attribute, blending stops in linear light by default
* Add a Space interpolation dropdown to the color picker popover
* Stamp legacy gradient ramps with their implicit gamma interpolation during deserialization
* Resolve color-interpolation from SVG style blocks and fix cascade order among repeated declarations
