Wiki Phase 1: categories, drafts/publish, HTML sanitization

Foundation & safety phase of the wiki upgrade (see WIKI_UPGRADE.md).

Schema (additive, idempotent via ensureSchema):
- new wiki_categories table; wiki_pages gains category_id, excerpt,
  published, published_at, sort_order, and a FULLTEXT index
- migration ALTERs guarded with IF NOT EXISTS for existing databases
- seed reworked into 4 sections with the 8 starter pages assigned

Security:
- new utils/sanitizeHtml.js (sanitize-html allowlist); wiki bodies are
  sanitized on every save, and the article renders through DOMPurify
- strips <script>, event handlers (onerror), and javascript: URLs

Backend:
- public: published-only list with ?category filter + /wiki/categories
- admin: extended page CRUD, PATCH publish toggle, category CRUD;
  drafts visible to admin, hidden from public
- all writes logged to activity_log

Frontend:
- data-driven public wiki index (sections + real descriptions; removed
  hardcoded blurbs/Roman numerals) with ?category filtering
- article: category breadcrumb + sanitized render
- admin: Section/Status columns, draft/publish + section + excerpt in the
  editor, and a Manage sections modal

Verified end-to-end against MariaDB 11: migration clean, XSS neutralized,
drafts hidden, client builds, server boots.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

server/src/model/wiki/wiki.model.js

@@ -1,20 +1,62 @@
 const wikiDb = require('./wiki.db')
+const { cleanBody } = require('../../utils/sanitizeHtml')
 
-async function list() {
-  return wikiDb.listSummaries()
+// ── Pages ──────────────────────────────────────────────────────────────
+async function listPublished(categoryId = null) {
+  return wikiDb.listPublishedSummaries(categoryId)
+}
+
+async function listAll(filters = {}) {
+  return wikiDb.listAllSummaries(filters)
 }
 
 async function getBySlug(slug) {
   return wikiDb.findBySlug(slug)
 }
 
-async function create({ slug, title, body, updatedBy }) {
-  await wikiDb.insert({ slug, title, body, updatedBy })
+async function getPublishedBySlug(slug) {
+  return wikiDb.findPublishedBySlug(slug)
+}
+
+async function create({ slug, title, body, excerpt, categoryId, published, updatedBy }) {
+  await wikiDb.insert({
+    slug,
+    title,
+    body: cleanBody(body),
+    excerpt: excerpt || null,
+    categoryId: categoryId ?? null,
+    published: published !== false, // default published unless explicitly false
+    updatedBy,
+  })
   return wikiDb.findBySlug(slug)
 }
 
-async function update(slug, { title, body, updatedBy }) {
-  await wikiDb.updateBySlug(slug, { title, body, updatedBy })
+// Partial update — only keys present in `input` are written. Body is sanitized;
+// published_at is stamped the first time a page goes live.
+async function update(slug, input) {
+  const current = await wikiDb.findBySlug(slug)
+  if (!current) return null
+
+  const fields = { updated_by: input.updatedBy ?? null }
+  if ('title' in input) fields.title = input.title
+  if ('body' in input) fields.body = cleanBody(input.body)
+  if ('excerpt' in input) fields.excerpt = input.excerpt || null
+  if ('categoryId' in input) fields.category_id = input.categoryId ?? null
+  if ('published' in input) {
+    fields.published = input.published ? 1 : 0
+    if (input.published && !current.published_at) fields.published_at = new Date()
+  }
+
+  await wikiDb.updateBySlug(slug, fields)
+  return wikiDb.findBySlug(slug)
+}
+
+async function setPublished(slug, published) {
+  const current = await wikiDb.findBySlug(slug)
+  if (!current) return null
+  const fields = { published: published ? 1 : 0 }
+  if (published && !current.published_at) fields.published_at = new Date()
+  await wikiDb.updateBySlug(slug, fields)
   return wikiDb.findBySlug(slug)
 }
 
@@ -22,4 +64,52 @@ async function remove(slug) {
   return wikiDb.deleteBySlug(slug)
 }
 
-module.exports = { list, getBySlug, create, update, remove }
+// ── Categories ─────────────────────────────────────────────────────────
+async function listCategories() {
+  return wikiDb.listCategories()
+}
+
+async function getCategoryBySlug(slug) {
+  return wikiDb.findCategoryBySlug(slug)
+}
+
+async function getCategoryById(id) {
+  return wikiDb.findCategoryById(id)
+}
+
+async function createCategory({ slug, title, description, sortOrder }) {
+  const id = await wikiDb.insertCategory({ slug, title, description, sortOrder })
+  return wikiDb.findCategoryById(id)
+}
+
+async function updateCategory(id, input) {
+  const fields = {}
+  if ('title' in input) fields.title = input.title
+  if ('slug' in input) fields.slug = input.slug
+  if ('description' in input) fields.description = input.description || null
+  if ('sortOrder' in input) fields.sort_order = input.sortOrder
+  await wikiDb.updateCategory(id, fields)
+  return wikiDb.findCategoryById(id)
+}
+
+async function removeCategory(id) {
+  return wikiDb.deleteCategory(id)
+}
+
+module.exports = {
+  list: listPublished, // back-compat alias (old callers expected published list)
+  listPublished,
+  listAll,
+  getBySlug,
+  getPublishedBySlug,
+  create,
+  update,
+  setPublished,
+  remove,
+  listCategories,
+  getCategoryBySlug,
+  getCategoryById,
+  createCategory,
+  updateCategory,
+  removeCategory,
+}