docs: extrude up to a surface in the literature, MCP and meshing skill (#400)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UhhZMBTviDQxZvwnyP89fo

docs/mcp.md

@@ -116,7 +116,7 @@ software on the computer.
 | `open` | `path`, `model?` | By extension: `.fieldcraft` (`file.open`), `.solidcraft` (`geometry.open`), `.3mf` (`geometry.import.mesh`). For a design, `model` is `keep` (default: the mesh and definitions stay, as a reopen after an edit wants) or `new` (a new model with the design); the reply's `related` is false when the design has none of the bodies the model refers to, and `stale` lists the mesh bodies and sets that no longer resolve. |
 | `save` | `path?` | `file.save`: to `path` or the model's own file. |
 | `write_deck` | `format` (abaqus, nastran, lsdyna), `path`, `steps?` | `deck.write`. |
-| `mesh` | `method`, `params?` | Runs the mesher (`tet`: `mesh.tet.generate`; `hex`, `hex_sweep`, `hex_mapped`, `hex_blocks`: the structured hex meshers; `cells`: `mesh.cells`, a partitioned part cell by cell; `mirror`: `mesh.mirror`, a meshed half reflected across a plane; `block`: `mesh.block`; `planar`: `mesh.planar`) and replies with its result, `model.info` and `mesh.quality`. |
+| `mesh` | `method`, `params?` | Runs the mesher (`tet`: `mesh.tet.generate`; `hex`, `hex_sweep`, `hex_mapped`, `hex_blocks`: the structured hex meshers; `hex_extrude`: `mesh.hex.extrude`, layers from a section up to a target surface; `cells`: `mesh.cells`, a partitioned part cell by cell; `mirror`: `mesh.mirror`, a meshed half reflected across a plane; `block`: `mesh.block`; `planar`: `mesh.planar`) and replies with its result, `model.info` and `mesh.quality`. |
 | `solve` | `analysis` (static, nonlinear, frequency, buckle, explicit, fluid, heat), `step?`, `options?` | `solve.<analysis>` with the step and the solver's caps and settings. |
 | `show_results` | `step?`, `field?`, `bands?`, `range?`, `deformed?`, `scale?`, `mode?`, `frame?`, `time?` | The `results.*` commands its arguments ask for (`deformed: false` draws the undeformed mesh; `scale` is a factor, 0 for the undeformed shape so a sequence from 0 swings the deformation out, or `"auto"`; `range: {min?, max?}` clamps the legend, values above `max` drawn in the over colour); the reply has the contour range (smallest and largest value and their nodes: `field: "displacement"` gives the largest displacement), modes or frames. |
 | `probe` | `step?`, `nodes?`, `at?`, `elements?`, `points?`, `forces?`, `mode?`, `frame?` | `solve.probe`: stored results at nodes, at the nodes nearest to points `at` (structural steps), elements (explicit) or points (fluid). |