v0.4.0

Visual Mapping Workspace

• New two-level visualisation in the VS Code extension: an overview mode with
  compact schema cards and thick mapping arrows, plus a focused mapping-detail
  view with source schemas, a central arrow table, and the target schema.
• Mapping-detail hover now cross-highlights rows and fields in both directions,
  making multi-schema joins and transforms much easier to inspect.
• Added pan/zoom reset on overview-to-detail transitions, smoother fade
  animation, a minimap, SVG export, mapping tooltips, and a cleaner toolbar.
• Schema cards now render metadata pills and Markdown notes, and the layout no
  longer fails when mappings reference missing ports.

VS Code Extension

• Added the new visualisation panel backed by the @satsuma/viz web component
  package and LSP-driven visual model extraction.
• Registered .satsuma files alongside .stm, added file icons, and grouped
  Satsuma commands coherently in the editor context menu.
• Fixed Find References for arrow paths and backtick NL references.
• Fixed bundled WASM runtime resolution so the packaged extension works
  reliably outside the development environment.

CLI And Distribution

• The CLI now ships as one universal release artifact built on WASM
  web-tree-sitter, removing platform-specific release packaging.
• Release packaging now builds the visualisation bundle before VSIX creation,
  fixing the missing @satsuma/viz asset issue in GitHub Actions.
• Install docs now reflect the single universal CLI package for all platforms.

Documentation

• Added the Feature 23 Phase 5 visual redesign plan and updated release-facing
  docs to reflect v0.4.0 and the current manual release flow.