Wiki Phase 4: full-text search + revision history

Final phase of the wiki upgrade (see WIKI_UPGRADE.md).

Schema (additive): wiki_revisions table (per-save content snapshots).
The FULLTEXT index on wiki_pages(title, body) shipped in Phase 1.

Search:
- MATCH ... AGAINST natural-language search over title + body, ordered by
  relevance
- public: GET /public/wiki?q= (published only); admin: GET /admin/wiki?q=
  (all statuses)
- public wiki index gains a search box; admin list gains a search field

Revision history:
- every create/update snapshots the page into wiki_revisions
- admin endpoints: list revisions, get one, and restore (restore overwrites
  the page, rebuilds links, and appends a new revision — history stays
  append-only); logged as wiki.revision.restore
- editor gains a History modal: revision list + word-level diff (jsdiff) of a
  chosen revision against the current page, with one-click restore

Verified end-to-end: search matches body and title; two edits produce three
revisions; diff renders added/removed words; restore reverts and records a new
revision. No console errors.

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

server/src/router/v1/admin/admin.controller.js

@@ -172,6 +172,9 @@ async function uploadFile(req, res) {
 // ── Wiki pages ─────────────────────────────────────────────────────────
 async function listWiki(req, res) {
   try {
+    const q = (req.query.q || '').trim()
+    if (q) return res.json(await wiki.search(q, { publishedOnly: false }))
+
     const filters = {}
     if (req.query.category) {
       const category = await wiki.getCategoryBySlug(req.query.category)
@@ -246,6 +249,7 @@ async function updateWiki(req, res) {
     if ('body' in req.body) input.body = req.body.body || null
     if ('excerpt' in req.body) input.excerpt = req.body.excerpt || null
     if ('published' in req.body) input.published = Boolean(req.body.published)
+    if ('change_note' in req.body) input.changeNote = req.body.change_note
     if ('tags' in req.body) input.tags = Array.isArray(req.body.tags) ? req.body.tags : []
     if ('category_id' in req.body) {
       const cat = await resolveCategoryId(req.body)
@@ -288,6 +292,45 @@ async function deleteWiki(req, res) {
   }
 }
 
+// ── Wiki revisions ─────────────────────────────────────────────────────
+async function listWikiRevisions(req, res) {
+  try {
+    const revisions = await wiki.listRevisions(req.params.slug)
+    if (revisions == null) return res.status(404).json({ message: 'Not found' })
+    return res.json(revisions)
+  } catch (err) {
+    log.error('listWikiRevisions', err)
+    return res.status(500).json({ message: 'Internal Server Error' })
+  }
+}
+
+async function getWikiRevision(req, res) {
+  try {
+    const rev = await wiki.getRevision(req.params.slug, Number(req.params.id))
+    if (!rev) return res.status(404).json({ message: 'Not found' })
+    return res.json(rev)
+  } catch (err) {
+    log.error('getWikiRevision', err)
+    return res.status(500).json({ message: 'Internal Server Error' })
+  }
+}
+
+async function restoreWikiRevision(req, res) {
+  try {
+    const page = await wiki.restoreRevision(req.params.slug, Number(req.params.id), req.user.id)
+    if (!page) return res.status(404).json({ message: 'Not found' })
+    await activity.log({
+      req,
+      action: 'wiki.revision.restore',
+      detail: { slug: req.params.slug, revision: Number(req.params.id) },
+    })
+    return res.json(page)
+  } catch (err) {
+    log.error('restoreWikiRevision', err)
+    return res.status(500).json({ message: 'Internal Server Error' })
+  }
+}
+
 // ── Wiki tags ──────────────────────────────────────────────────────────
 async function listWikiTags(req, res) {
   try {
@@ -488,6 +531,9 @@ module.exports = {
   updateWiki,
   publishWiki,
   deleteWiki,
+  listWikiRevisions,
+  getWikiRevision,
+  restoreWikiRevision,
   listWikiTags,
   listWikiCategories,
   createWikiCategory,

server/src/router/v1/admin/admin.routes.js

@@ -114,6 +114,7 @@ adminRouter.put(
   body('category_id').optional({ values: 'null' }).isInt(),
   body('published').optional().isBoolean(),
   body('tags').optional().isArray(),
+  body('change_note').optional({ values: 'falsy' }).isString().isLength({ max: 280 }),
   validate,
   ctrl.updateWiki,
 )
@@ -123,6 +124,14 @@ adminRouter.patch(
   validate,
   ctrl.publishWiki,
 )
+adminRouter.get('/wiki/:slug/revisions', ctrl.listWikiRevisions)
+adminRouter.get('/wiki/:slug/revisions/:id', param('id').isInt(), validate, ctrl.getWikiRevision)
+adminRouter.post(
+  '/wiki/:slug/revisions/:id/restore',
+  param('id').isInt(),
+  validate,
+  ctrl.restoreWikiRevision,
+)
 adminRouter.delete('/wiki/:slug', ctrl.deleteWiki)
 
 // ── Settings ──────────────────────────────────────────────────────────