mesh.hex.blocks: one conforming hex mesh of a design split into blocks

Meshes the open design's bodies (or the listed ones) as the cells of one
conforming all-hex mesh with one size and tessellation tolerance for all;
elements carry their cell's body, boundary faces its B-rep faces. A cell
that is no block, or cells that touch without sharing whole faces, is an
error naming the bodies. Catalogue entry with its VectorCraft icon, the
MCP mesh tool's hex_blocks method, docs/features.md.

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm

docs/features.md

@@ -6,7 +6,7 @@ Every entry is a toolbar button. **Ready** entries run their command; **coming s
 shown greyed with the roadmap milestone that brings them (ROADMAP.md). Scripts, the command line,
 the control channel and AI agents over MCP (docs/mcp.md) run the same commands.
 
-54 ready, 49 coming soon.
+55 ready, 49 coming soon.
 
 ## Geometry
 
@@ -35,6 +35,7 @@ the control channel and AI agents over MCP (docs/mcp.md) run the same commands.
 | Structured Hex | Quad Faces — All-quad meshes of faces on shared edge nodes | coming soon (M5) |  |
 | Structured Hex | Mapped Hex — Mapped hex mesh of a six-sided block (curved faces allowed) | ready | `mesh.hex.mapped`, `mesh.hex.generate` |
 | Structured Hex | Sweep Hex — Hex mesh swept along extrusions (several levels), around revolutions, or from a source face to a target | ready | `mesh.hex.sweep`, `mesh.hex.generate` |
+| Structured Hex | Block Hex — One conforming hex mesh of a part split into six-sided blocks: shared faces meshed once | ready | `mesh.hex.blocks` |
 | Structured Hex | Decompose — Find sweepable and mappable regions and propose the splits | coming soon (M5) |  |
 | Structured Hex | Transition — Conforming tet–hex interfaces with pyramids | coming soon (M5) |  |
 | Automatic Hex | All-Hex — Octree dual all-hex mesh of any part | coming soon (M6) |  |