Add a content kind

A kind is one folder. src/entities/<kind>/kind.ts describes it once (its id, labels, deck color and glyph, whether it
is a Library deck, the blank piece "New" saves, the lines bunzai inspect prints), plus, when they apply, the
pieces it links by id (links), where its name lives (namePath), where it keeps pictures (media), whether it is
too heavy to read whole (heavy), whether the Library offers "New" for it (libraryNew), which scene field
points at it (sceneField), which list in a scene's prompting links it (promptingList), the Workbench editor it opens in, and, for a kind in a family, the deck it joins (deck,
with the owning kind's deckTitle and deckBlurb) and how it reads as its family's base (asPreset and
sendProblem for a writing setup, src/core/writing.ts). Then bun run kinds
(scripts/kind-manifest.ts) writes two static seams from every kind folder:

• src/generated/kinds.ts: KINDS, KIND_IDS, kindOf, isKindId, and AnyKindEntity, the union of every kind's
  canonical piece. No decoder code, so the browser bundle and the search worker load it cheaply.
• src/generated/kind-schemas.ts: every kind's whole-entity decoder (the parse boundary's discriminated union) and the
  kinds whose bodies split into item parts in storage.

Both are checked by bun run kinds:check in verify:ci; never edit them by hand.

What reads the seam (so you edit none of it)

What	Where
The closed set of studio folders	src/studio/path-policy.ts (STUDIO_ENTITY_KINDS)
The parse boundary	src/entities/runtime-schema.ts
Storage item parts	src/entities/piece-parts.ts
Format adapter contracts	src/core/adapter.ts (KindAdapter<K>; character and preset add their extras)
Deck labels, colors, glyphs, Library decks	src/ui/_shared/decks.ts
Panel, editor head and Press deck colors	components/panel, components/editor-ehead, apps/press (inline from deckMeta)
Search kind: words	src/core/search/kind-aliases.ts (plural, short tag, searchWords)
Import receipts	src/ui/receipt.ts (receiptWord)
Kit deck counts and name lookup	src/kit/bridge.ts, src/kit/tools/rail-open.ts
Library "New" and every other blank-piece door	src/ui/_shared/new-piece.ts (createBlank, from blank and blankId; canCreateBlank honors libraryNew)
Links: Press riders, export embedding, import renames, Kit delete warnings, Workbench node ports, archive link caveats	src/core/links.ts (from links and sceneField)
A piece's name, read and written	src/core/piece-name.ts (from namePath)
Which paths are pictures, which kinds carry art	src/entities/_shared/media-reference.ts (from media; Kit's gallery and art tools read ART_KINDS)
Duplicate, rename and the Press on heavy pieces	src/ui/apps/press, src/ui/apps/library/delete-flow.tsx (from heavy)
bunzai inspect	src/cli-inspect.ts (describe)
First-run deck titles	src/ui/setup/steps/first-deck
Format matrix and field docs	scripts/format-matrix.ts, scripts/docs-fields.ts

Steps

1. Make src/entities/<kind>/ with schema.ts (the canonical type CanonicalEntity<"<kind>", Body> and an empty-body
   factory) and runtime-schema.ts (the strict body decoder wrapped in defineExhaustiveShape, and
   export const entitySchema = z.strictObject(defineExhaustiveShape<CanonicalX>()(entityShape("<kind>", bodySchema, profileSchema)))).
2. Write src/entities/<kind>/kind.ts: export default defineKind<"<kind>", Body>({ ... }). The accent must be a
   --deck-* token in src/ui/theme/tokens.css; the icon a glyph id from src/generated/ic-glyphs.json.
3. Optional: parts.ts when the body has a long item list that should save item by item (see kind-parts.ts), and
   capabilities/ for Kit (bun run capabilities).
4. Run bun run kinds.
5. Name the kind's Workbench editor in its kind.ts (editor: an id, a label and how much of the piece it reads),
   then add the component to src/ui/apps/workbench/editors.ts under that id. The completeness test fails on a
   named editor with no component, and on a component no kind names.
6. Write docs/reference/entities/<kind>.md and scripts/scale/fixtures/<kind>.ts.
7. Run bun test src/entities/kind-completeness.test.ts. It lists, per kind, every missing part and the file to
   create. A part a kind deliberately goes without (an editor, Kit capabilities) is named in the test's exemption list
   with the reason.

Behavior that belongs to one kind alone (a preset's readiness line in the Press, a lorebook's scan) stays in the code
that owns that behavior; the hub is for what every kind has. A scene's own fields (its preset with toggles and samplers,
its lorebook choices, its regex rack, its backdrop) keep their own shapes and rules in the scene store; sceneField
only says that a scene can point at the kind.

src/entities/kind-lists.test.ts keeps it that way: a source line naming two or more kind ids is a hand-written list,
and every file holding one is listed there with its count and the reason it is not a kind list. Read the hub instead of
adding to it.