[prakashUXtech]

This is the last PR of #435 (fill-tools, slice FT-z). Closes #435.

What

docs/blueprints/core/features/fill-tools.md (FT-8): the status line now says built.

It lists the merged slice PRs:

• test(fill): seeded scenes and analytic gradient values for the fill-tools checks #568, feat(fill): declare the fill-tools contract stubs #589, test(raster): fill-tools checks first, disabled until FT-3 to FT-5 #595 (FT-a)
• feat(raster): scanline flood-fill mask with tolerance, global mode and soft edge #608, feat(raster): colour range mask and box-mean colour sample #623 (FT-mask)
• feat(raster): gradient shapes and OKLab stop interpolation #612, feat(raster): ordered dither for raster gradients #622 (FT-grad)
• test(fill): KJ-FT walk and fill budgets #654 (FT-z)

It also lists the review fixes: #649, #650, #683, #688, #689, #765, #766.

It records where the code differs from the packet:

• The KJ-FT walk checks the gradient buffer on its own, because masks-mattes is not on dev yet. The masked-composite step is perf(fill): flood fill, colour range and gradient over their release budgets; walk the bucket through the masked composite #767.
• The release budgets run and report, and a miss is recorded as a known issue. Flood fill, colour range and the gradient are still over budget on Linux (perf(fill): flood fill, colour range and gradient over their release budgets; walk the bucket through the masked composite #767). The Mac finisher times them.
• The 2 bytes per pixel bound is checked on every platform as the flood fill's counted scratch. The resident peak is only printed.
• GradientSpace.linear keeps its name and means linear-light mixing.
• gradient and gradientMap share one public PixelBuffer.maxGradientStops and one hard-edge rule.
• Dither applies to the straight colour, before premultiplying.

Why

FT-z closes the feature: the walk and the budgets are already on dev, and this PR marks the packet built.

Tests

This PR changes docs only. scripts/ci printed CI: PASS on this head, rebased on dev cc27761. The packet's check for FT-8 is "status line says built".

Belt-Lead: act-1a157fd0281-warg
Feature: fill-tools
Slice: FT-z
Mutate: 0/0 none (docs only)
Fast-Check: pass
Head: d188166

[github-actions]

Fast lane: merged into dev (15 lines, 1 files, Fast-Check marker).