revert: undo the UI kit and AI design guidance work (#1414) (#1417)

Reverts 09f8134 in full. The tree is byte-identical to the commit before it,
produced by git revert rather than by hand so nothing is left behind.

The token layer was the part that looked most defensible and it is the part
that settles this. @webjsdev/ui exists for shadcn parity, and measured against
the shadcn clone every token change in that PR moved away from it. shadcn
ships no --success, --warning or --info, so those twelve tokens were an
invention. It uses Tailwind's stock shadow scale at the call site, so renaming
seventeen usages to a shadow-e1 through shadow-e4 role scale was churn against
parity, and it forced a cn() classifier change in three copies to support a
name shadcn does not have.

The destructive contrast fix is the sharpest case. shadcn's own values are
byte-identical to what the kit already had, light oklch(0.97 0.01 17) and dark
oklch(0.58 0.22 27), and shadcn's button never reads the token: it carries
text-white, exactly as this kit did. So the pair that PR called a live bug is
upstream parity, latent by design on both sides, and the change would have put
a real regression on the button until review caught it.

The rest goes for reasons that were visible earlier and that I did not act on.
The six primitives each composed from helpers the kit already had. The two
example screens were single static screens listed beside a real composed app.
The design reference was explicitly the unproven half and its owner-run gate
never ran, so it shipped measuring nothing, and the evaluation harness exists
only to run that gate. The header blocks carry the same unproven premise into
every user's repo. The gallery payload rescaling edited working demos to
satisfy a rubric that PR introduced.

One genuine parity gap surfaced on the way and is NOT addressed here, since
adding it inside a revert would be the same mistake again: shadcn ships
--surface, --surface-foreground, --code, --code-foreground and --selection,
and this registry theme has none of them.

Author: vivek7405

.agents/skills/webjs/SKILL.md

@@ -67,8 +67,6 @@ Rows point rather than explain. The reference is the authority on the rule, and
 | accept an upload and serve it back | `FileStore` plus a streaming route | buffering the file in memory or writing to `public/` | `references/built-ins.md` | `app/features/file-storage` |
 | keep the app usable offline | the opt-in service worker | caching responses in `localStorage` | `references/service-worker.md` | `app/features/service-worker` |
 | see these composed in one real feature | the todo example app | stitching the single-feature demos together | `references/optimistic-ui.md` | `app/examples/todo` |
-| work out what a screen should look like before writing the class list | the design reference, then the dashboard exemplar | making everything the same weight and hoping it reads | `references/design.md` | `app/examples/dashboard` |
-| make a long form fillable rather than a column of inputs | grouping by fieldset, with reserved error space | one flat list of every field the model has | `references/design.md` | `app/examples/settings` |
 
 ## Load Only The References You Need
 
@@ -82,8 +80,6 @@ The table above routes by the job; this one routes by the topic, for when you al
 | Server actions, mutations, queries, validation, the `ActionResult` envelope | `references/data-and-actions.md`              |
 | Sessions, login flows, route protection, `forbidden()` / `unauthorized()`   | `references/auth-and-sessions.md`             |
 | Tailwind, light-DOM tag-prefix rule, tokens, fixed headers, no-reflow layout | `references/styling.md`                        |
-| **Designing a screen** (READ FIRST when building any user-facing screen): hierarchy, the action pyramid, spacing rhythm, type scale, palette, elevation, empty states | `references/design.md`                         |
-| Palette construction from an accent, the component-variant checklist, finishing touches | `references/design-depth.md`                   |
 | Client router, prefetch, frames, view transitions, Suspense streaming        | `references/client-router-and-streaming.md`   |
 | Optimistic UI for a user-facing mutation                                     | `references/optimistic-ui.md`                 |
 | The `@webjsdev/ui` component kit (a `components.json` is present): class helpers, tokens, `add` / `view`, the MCP `ui` tool | `references/ui-kit.md`                         |