feat(showcase): add road-bicycle (vehicles)

The fifth piece in the vehicles category: a 1970s lugged-steel road
bicycle leaning 5 deg onto its side kickstand. A 56 cm diamond frame in
chromed spear-point lugs, tapered stays with chrome tips, a chrome-crowned
fork; 700c wheels of 36 spokes laced three-cross from both flanges to
nipples through box-section rims, QR skewers, tan-wall tyres; 52/42
crankset with quill pedals and toe clips, six-speed freewheel, a roller
chain of 112 individual links solved round ring, cog and both jockeys,
front and rear derailleurs, down-tube shifters, side-pull calipers,
gum-hooded levers on cotton-taped drop bars, quill stem, leather saddle,
a bottle in a bolted wire cage. Ten materials; metals carry the
espresso-machine reflection studio.

Budgets (measured, 5.2.1): 46092 tris (45600-46600), LOD 0.4995/0.2198,
10 materials with face floors, UVs 0..1 no overlap, AABB
1.6698x0.4376x0.9969 (1.670x0.438x0.997 +-0.01), collider 880 (<=970),
hygiene 0 incl. 0 coplanar cross-shell pairs, tyres and foot zmin 0,
hubs 0.000 mm off dropout eyes, spokes 3.00 mm into flanges and 4.50 mm
into nipples, rims 0.000 mm off the frame plane, seat tube 0.5800 m,
wheelbase 0.99982 m, trail 0.05536 m, lacing 36/36 18/18 pitch 0.000
deg cross 60.000 deg, 30 + 10 rollers seated 1.20-3.40 mm above root,
chain line 0.000 mm, stance margin 0.0393 m at 11.80 kg, 1 component
(685 shells). Two default runs print identical measurements.

Falsifiers (flag -> measured -> exit): --skip-decimate LOD1 1.0000 -> 9;
--stray-vert loose_v 1 -> 15; --lift-z zmin 0.05000 -> 16; --float-tyre
rear tyre zmin 0.003 -> 16; --slip-wheel hub 0.00200 m off eye -> 17;
--short-spoke end -0.00150 inside nipple -> 18; --dish-wheel rim 0.00299
m off plane -> 19; --steep-head trail -0.02926 m -> 20; --bunch-spokes
pitch 4.000 deg -> 21; --lift-chain seat up to 8.11 mm -> 22;
--shift-rollers roller 0.00150 m off the line -> 23; --tuck-stand margin
-0.0062 m -> 24; --pop-bottle 2 components [2, 683] -> 25. Every one
leaves the triangle count at 46092 and the budgets before it green.

Blender: E:\Blender-Developer-Tools\.scratch\5.2\blender-5.2.1-windows-x64\blender.exe,
reports "Blender 5.2.1 LTS". 4.5 LTS left to CI.

Render: render_hero.py wrote hero and preview; framing fill x 0.666,
y 0.778, margins >= 0.111; asset-quality floors pass (edge90 0.099).

Asset sheet (docs/gallery/asset-sheets/road-bicycle.webp): not the
least-designed object in the lineup; the hydrant and the wheelbarrow are
plainer. Isolated it reads at once as a lugged road bike: lugs, laced
wheels, tan walls, saddle, taped bars, chain and derailleurs all carry.
Weak point: a long thin object, it fills little of its panel.

Contact sheet (docs/gallery/contact-sheets/road-bicycle-contact-sheet.webp):
luma 0.2382 against 0.2369-0.2428 (in band; first draft 0.2556, relit
with a dimmer key and wedge). Stage 0.1952 against 0.1919-0.2517 (in
band). Saturation 0.2335 against 0.1525-0.2367 (in band). Wedge warmth
+0.0872 against -0.1440/+0.1052/+0.0921 (inside the spread). Thumbnail
legible.

Also updated: README, CLAUDE.md, AGENTS.md counts (55 -> 56), ROADMAP
Vehicles list (road bicycle struck as shipped), asset_sheet.py SELECT
row, catalog.json, plugin.json and the regenerated gallery.
build_gallery, check_site_links (111 pages, 0 failures),
check_falsifier_targets, check_exit_code_readme, check_engine_id,
check_gallery_images and check_import_export_rules pass.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

Author: TMHSDigital

.cursor-plugin/plugin.json

@@ -193,6 +193,7 @@
     "showcase/cargo-loader",
     "showcase/archery-target",
     "showcase/cactus-garden",
-    "showcase/espresso-machine"
+    "showcase/espresso-machine",
+    "showcase/road-bicycle"
   ]
 }

AGENTS.md

@@ -21,7 +21,7 @@ classifies it as a `cursor-plugin`. This is content the AI loads when the user
 asks Blender questions or works on Blender add-ons in Cursor or Claude Code.
 
 The content base is 16 skills, 9 rules, 3 templates, 27 snippets, 60
-examples, and 55 showcase pieces (counts are CI-enforced against README.md)
+examples, and 56 showcase pieces (counts are CI-enforced against README.md)
 and the manifest). The full inventory tables and per-item purposes live in
 `CLAUDE.md`. Example anatomy and authoring rules: copy `examples/bmesh-gear/`;
 showcase conventions: `showcase/README.md`. The render look is specified

CLAUDE.md

@@ -22,7 +22,7 @@ rules/<rule-name>.mdc          - Anti-pattern rules, 9 total
 templates/<template-name>/     - Starter projects, 3 total
 snippets/<snippet-name>.py     - Standalone code patterns, 27 total
 examples/<name>/               - Runnable smoke-gated examples, 60 total (+ gallery.json)
-showcase/<name>/               - Budget-conformance props, 55 pieces, each with a gallery `category` (sibling of examples/; see showcase/README.md § Categories)
+showcase/<name>/               - Budget-conformance props, 56 pieces, each with a gallery `category` (sibling of examples/; see showcase/README.md § Categories)
 scripts/build_gallery.py       - Regenerates docs/gallery/ from examples/gallery.json + showcase/gallery.json
 scripts/site/                  - Vendored landing-page build (Jinja2); tokens.css is the shared palette
 tests/check_site_links.py      - Internal link/anchor/alt gate over the built site (docs/)

README.md

@@ -18,7 +18,7 @@
 </p>
 
 <p align="center">
-  <strong>16 skills</strong> &nbsp;&bull;&nbsp; <strong>9 rules</strong> &nbsp;&bull;&nbsp; <strong>3 templates</strong> &nbsp;&bull;&nbsp; <strong>27 snippets</strong> &nbsp;&bull;&nbsp; <strong>60 examples</strong> &nbsp;&bull;&nbsp; <strong>55 showcase pieces</strong>
+  <strong>16 skills</strong> &nbsp;&bull;&nbsp; <strong>9 rules</strong> &nbsp;&bull;&nbsp; <strong>3 templates</strong> &nbsp;&bull;&nbsp; <strong>27 snippets</strong> &nbsp;&bull;&nbsp; <strong>60 examples</strong> &nbsp;&bull;&nbsp; <strong>56 showcase pieces</strong>
 </p>
 
 <p align="center">
@@ -37,7 +37,7 @@
 
 ## Overview
 
-This repository ships **16 skills, 9 rules, 3 templates, 27 snippets, 60 examples, and 55 showcase pieces** for Blender Python development targeting Blender 5.2 LTS (current stable) with Blender 4.5 LTS fallback support. Blender 5.1 is prior stable.
+This repository ships **16 skills, 9 rules, 3 templates, 27 snippets, 60 examples, and 56 showcase pieces** for Blender Python development targeting Blender 5.2 LTS (current stable) with Blender 4.5 LTS fallback support. Blender 5.1 is prior stable.
 
 The content is consumed by AI coding agents reading these files directly from a checkout — **there is no MCP server in this repository, and none is required**. Cursor applies `rules/*.mdc` automatically wherever their scope globs match and takes skills by name in chat; Claude Code reads `skills/` and `rules/` from the project workspace, or from this repo kept as a referenced checkout. Any agent that can read files in a workspace can use it the same way. There is no build step for the content — edit the Markdown and Python files directly.
 
@@ -106,7 +106,7 @@ per-script exit-code model, are in
 Budget-conformance props. Not examples. Conventions: [`showcase/README.md`](showcase/README.md).
 
 <details>
-<summary><strong>55 showcase pieces</strong> — click to expand the preview grid</summary>
+<summary><strong>56 showcase pieces</strong> — click to expand the preview grid</summary>
 
 <p align="center">
   <a href="showcase/shipping-crate/"><img src="showcase/shipping-crate/preview.webp" width="24%" alt="Shipping crate: a wooden slat crate stencilled PORT ROYAL and NO 17, with iron corner brackets and an end handle, on a dark studio floor, warm wedge on the back wall" /></a>
@@ -164,6 +164,7 @@ Budget-conformance props. Not examples. Conventions: [`showcase/README.md`](show
   <a href="showcase/archery-target/"><img src="showcase/archery-target/preview.webp" width="24%" alt="Archery target: a straw boss with a gold, red, blue, black and white face and five arrows, leaning on a timber easel numbered 12 with a hinged rear leg and a splay chain, on a turf patch with a leather quiver and a snapped arrow in the grass, on a dark studio floor" /></a>
   <a href="showcase/cactus-garden/"><img src="showcase/cactus-garden/preview.webp" width="24%" alt="Cactus garden: a ribbed saguaro with three arms, rows of spines and cream flowers on its crown, a barrel cactus with red hooked spines and yellow fruit, a prickly pear with magenta fruit, an agave rosette and sandstone rocks on a raised sand disc, on a dark studio floor" /></a>
   <a href="showcase/espresso-machine/"><img src="showcase/espresso-machine/preview.webp" width="24%" alt="Espresso machine: a brushed stainless E61 espresso machine with twin gauges, a chrome group head and a walnut-handled portafilter over a shot cup, cups on its warmer tray, beside a tamper, milk pitcher and knock box on a stone counter" /></a>
+  <a href="showcase/road-bicycle/"><img src="showcase/road-bicycle/preview.webp" width="24%" alt="Road bicycle: a deep red lugged-steel road bicycle leaning on its kickstand, with chromed lugs and fork socks, tan-wall 700c wheels, a honey leather saddle, cream-taped drop bars and a chain over a double crankset" /></a>
 </p>
 
 [`shipping-crate`](showcase/shipping-crate/) — procedural crate through UVs, bake, LOD, collider, and Unity glTF, asserting recomputed budgets. Falsifier `--skip-decimate` exits 9.
@@ -272,6 +273,8 @@ Budget-conformance props. Not examples. Conventions: [`showcase/README.md`](show
 
 [`espresso-machine`](showcase/espresso-machine/) — the fifth `household` piece: procedural prosumer E61 espresso machine on a honed stone countertop section (a black chassis behind a brushed stainless front panel, side panels folded round its edges with louvred vent slots cut through each sheet, a warmer tray with a bent rail and four upturned cups, adjustable feet; the chromed E61 group with its neck, gasket, mushroom cap and a lever pinned through two bosses; a spouted portafilter with a walnut handle; steam and hot-water valves with fluted bakelite knobs and wands on ball joints; twin gauges with printed dials in chrome bezels; a toggle and pilot lamp; a drip tray whose slotted grate carries a shot cup of espresso; a knock box, a tamper and a milk pitcher), whose feet on the counter, lever pin coaxial through its bosses, cups seated on their hosts, body size, portafilter coaxial and seated to the gasket, gauge glasses recessed in their bezels, drip tray inside the footprint, mass centre inside the feet and single connected assembly are recomputed from the mesh, through the same pipeline. Falsifiers `--float-foot` exits 16, `--offset-pin` 17, `--sink-cup` 18, `--narrow-body` 19, `--offset-pf` 20, `--drop-pf` 21, `--proud-gauge` 22, `--shift-tray` 23, `--bunch-feet` 24, `--loose-knob` 25.
 
+[`road-bicycle`](showcase/road-bicycle/) — the fifth `vehicles` piece: procedural 1970s lugged-steel road bicycle leaning on its side kickstand (a 56 cm diamond frame in chromed, spear-pointed lugs, tapered stays with chrome tips, a chrome-crowned fork with socks; two 700c wheels of 36 spokes laced three-cross from both flanges of small-flange hubs to nipples through box-section rims, quick-release skewers, tan-wall tyres with a file-tread crown; a 52/42 crankset with quill pedals, toe clips and straps, a six-speed freewheel and a roller chain of 112 individual links solved round the ring, the cog and both jockeys; front and rear derailleurs, down-tube shifters, side-pull calipers, gum-hooded levers on cotton-taped drop bars, a quill stem, a leather saddle on rails, a bottle in a bolted cage), whose hubs coaxial with their dropouts, spoke seats in flange and nipple, wheels in the frame's plane, steering trail, three-cross lacing, chain seated on ring and cog, straight chain line, mass centre inside the tyres-and-foot triangle and one connected assembly are recomputed from the mesh, through the same pipeline. Falsifiers `--float-tyre` exits 16, `--slip-wheel` 17, `--short-spoke` 18, `--dish-wheel` 19, `--steep-head` 20, `--bunch-spokes` 21, `--lift-chain` 22, `--shift-rollers` 23, `--tuck-stand` 24, `--pop-bottle` 25.
+
 </details>
 
 ## Examples