docs(base-sync): align deepslate header and registry with stone contract (#240)

[BharathASL]

Description

Align the deepslate base-sync header and registry entry with the stone contract (#240). Documents that derivatives copy the (currently empty) block along with , enforces single-line formatting of sharedSections in tools/base-sync.json, and adds unit test coverage for header wording, formatting invariants, and missing detection.

Affected Assets

• textures/block/deepslate.svg

---

Type of Change

• feat: New vector texture master, blockstate, or compiler capability
• fix: Tiling fix, palette correction, or bugfix
• docs: Documentation improvement
• chore / refactor: Maintenance, dependencies, or codebase cleanup

---

Contributor Checklist

Please check all applicable boxes before requesting review:

Vector Texture Standards (if adding/modifying SVGs)

• Authored as a clean $512\times512$ SVG (viewBox="0 0 512 512").
• Primary shapes are aligned to the $32\text{px}$ texel grid ($16\times16$ grid).
• Seamless Toroidal Tiling: Checked and verified that elements wrapping across $X$ and $Y$ edges align perfectly without seams or chopped shapes.
• Ore Consistency: If adding an ore texture, the stone background geometry and corner radius (rx) match textures/block/stone.svg exactly.
• Free of leftover AI generation comments, unnecessary editor namespaces, or embedded raster images.

Build & Verification

• Ran npm run build locally and verified that the pack compiles successfully.
• Verified textures in-game or inspected the rasterized PNG outputs in dist/.

Git Hygiene & Standards

• Commit message(s) follow Conventional Commits (e.g., feat(textures): ...).
• Every commit is signed off with the Developer Certificate of Origin (git commit -s).
• Branch is rebased cleanly onto latest main with no merge commits.
• Formatting complies with .editorconfig (2-space indent, LF endings, trailing newline).

[ninja6-agent]

No issues found.