feat(world): parseItem extracts optional ## read / lit / extinguished / lighter-empty sections

Existing items with no body sections continue to load unchanged. New items
can author per-state prose in dedicated sections; the dispatcher will read
these in subsequent commits.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/world/loader.test.ts

@@ -311,6 +311,118 @@ describe('narration registry', () => {
   })
 })
 
+describe('parseItem — body sections', () => {
+  it('extracts ## read into readableText', () => {
+    const md = `---
+id: letter
+names: [letter, note]
+short: a folded letter
+takeable: true
+readable: true
+---
+
+A folded letter, sealed with wax.
+
+## read
+You loved Halfstreet, the letter says. I loved it too.
+`
+    const item = parseItem(md, 'items/letter.md')
+    expect(item.long).toBe('A folded letter, sealed with wax.')
+    expect(item.readable).toBe(true)
+    expect(item.readableText).toBe('You loved Halfstreet, the letter says. I loved it too.')
+  })
+
+  it('extracts ## lit and ## extinguished', () => {
+    const md = `---
+id: lamp
+names: [lamp]
+short: an oil lamp
+takeable: true
+lightable: true
+initialState:
+  lit: false
+---
+
+An iron oil lamp.
+
+## lit
+The wick catches; warm yellow light fills the space.
+
+## extinguished
+You smother the flame. The room darkens.
+`
+    const item = parseItem(md, 'items/lamp.md')
+    expect(item.long).toBe('An iron oil lamp.')
+    expect(item.litText).toBe('The wick catches; warm yellow light fills the space.')
+    expect(item.extinguishedText).toBe('You smother the flame. The room darkens.')
+  })
+
+  it('extracts ## lighter-empty', () => {
+    const md = `---
+id: matches
+names: [matches]
+short: a matchbook
+takeable: true
+lighter: true
+lighterUses: 4
+---
+
+A matchbook from the Halfstreet Hotel.
+
+## lighter-empty
+The last match flares and dies. The book is empty.
+`
+    const item = parseItem(md, 'items/matches.md')
+    expect(item.lighterEmptyText).toBe('The last match flares and dies. The book is empty.')
+  })
+
+  it('throws when readable: true but ## read is missing', () => {
+    const md = `---
+id: x
+names: [x]
+short: x
+takeable: true
+readable: true
+---
+
+A thing.
+`
+    expect(() => parseItem(md, 'items/x.md')).toThrow(/## read.*required when readable/i)
+  })
+
+  it('still parses items with no body sections (back-compat)', () => {
+    const md = `---
+id: lamp
+names: [lamp]
+short: an oil lamp
+takeable: true
+---
+
+An iron oil lamp with a glass chimney.
+`
+    const item = parseItem(md, 'items/lamp.md')
+    expect(item.long).toBe('An iron oil lamp with a glass chimney.')
+    expect(item.readable).toBeUndefined()
+    expect(item.readableText).toBeUndefined()
+  })
+
+  it('throws for unknown section keys', () => {
+    const md = `---
+id: x
+names: [x]
+short: x
+takeable: true
+---
+
+A thing.
+
+## badkey
+Content.
+`
+    expect(() => parseItem(md, 'items/x.md')).toThrow(/unknown item section "## badkey".*Allowed:.*read.*lit.*extinguished.*lighter-empty/i)
+  })
+})
+
 describe('parseRoom invalid headers', () => {
   it('throws a clear error when a header has spaces', () => {
     const md = `---

src/world/loader.ts

@@ -130,22 +130,52 @@ export function parseRoom(raw: string, sourcePath: string): Room {
   return room
 }
 
+const ITEM_SECTION_KEYS = ['read', 'lit', 'extinguished', 'lighter-empty'] as const
+type ItemSectionKey = typeof ITEM_SECTION_KEYS[number]
+
 export function parseItem(raw: string, sourcePath: string): Item {
   const parsed = matter(raw)
   const frontmatter = stripWikilink(parsed.data) as Record<string, unknown>
   const fm = itemFrontmatterSchema.parse(frontmatter)
-  const long = parsed.content.trim()
-  if (long.length === 0) {
+
+  // Split body into long-description prefix + sectioned remainder.
+  // The first `## key` header (if any) marks the boundary.
+  const body = parsed.content
+  const firstHeader = body.match(/^##\s+[\w-]+\s*$/m)
+  const longRaw = firstHeader ? body.slice(0, firstHeader.index!).trim() : body.trim()
+  if (longRaw.length === 0) {
     throw new Error(`${sourcePath}: empty long description`)
   }
-  return {
+  const sections = firstHeader ? splitSections(body.slice(firstHeader.index!)) : {}
+
+  // Validate that only known section keys appear.
+  for (const key of Object.keys(sections)) {
+    if (!ITEM_SECTION_KEYS.includes(key as ItemSectionKey)) {
+      throw new Error(`${sourcePath}: unknown item section "## ${key}". Allowed: ${ITEM_SECTION_KEYS.join(', ')}`)
+    }
+  }
+
+  if (fm.readable && !sections['read']) {
+    throw new Error(`${sourcePath}: ## read section is required when readable: true`)
+  }
+
+  const item: Item = {
     id: fm.id,
     names: fm.names,
     short: fm.short,
-    long,
+    long: longRaw,
     initialState: fm.initialState,
     takeable: fm.takeable,
   }
+  if (fm.readable !== undefined) item.readable = fm.readable
+  if (fm.lightable !== undefined) item.lightable = fm.lightable
+  if (fm.lighter !== undefined) item.lighter = fm.lighter
+  if (fm.lighterUses !== undefined) item.lighterUses = fm.lighterUses
+  if (sections['read']) item.readableText = sections['read']
+  if (sections['lit']) item.litText = sections['lit']
+  if (sections['extinguished']) item.extinguishedText = sections['extinguished']
+  if (sections['lighter-empty']) item.lighterEmptyText = sections['lighter-empty']
+  return item
 }
 
 export interface ParsedEnding {