chore(quality): resolve SonarQube code smells across website

Clears the 124 CODE_SMELL findings from the SonarQube scan (server, client,
and bot). All changes are behaviour-preserving refactors — no route, protocol,
schema, or config changes — verified against the full server (381) and client
(43) test suites plus a clean client build.

By rule:
- S3776 (20, cognitive complexity): extract helpers/handlers so each function
  drops under the threshold — shard model upsert builders, page/wiki update,
  block validation, notification stream mapping (dispatch table), SSO mobile
  login, shard ingest deps, uo-link socket backfill/connect, the bot slash-
  command dispatchers + discord manager, and the Shard/UserDetail/HeroEditor/
  CharacterStats React components.
- S4624 (34, nested template literals): pull inner templates into locals /
  a withQs() helper; rewrite shardEvents.describe() as a formatter table.
- S3358 (35, nested ternaries): lift to if/else vars, lookup maps, small
  components, or guarded JSX expressions.
- S6479 (12, array-index React keys): key by stable content instead of index
  (two in-editor lists left as-is; index matches their by-index edit model).
- S6353 (6): [0-9]/[^0-9] -> \d/\D.  S125 (5): reword state-shape comments that
  parsed as code.  S3800/S3782 (botScore): JSDoc-type PATH_WEIGHTS tuples.
- S6481 (2): memoize Auth/Site context values (and SiteContext brand).
- S4144: dedupe HeroEditor upload handler into useImageUpload().
- S1126 (2), S6035, S5869 (redundant A-Z under /i), S5843 (town-name regex ->
  prefix list): assorted one-liners.

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

client/src/routes/admin/views/WikiHistory.jsx

@@ -80,11 +80,11 @@ export default function WikiHistory({ slug, onClose, onRestored }) {
         </>
       }
     >
-      {loading ? (
-        <span className="spin" />
-      ) : error ? (
+      {loading && <span className="spin" />}
+      {!loading && error && (
         <p className="sans" style={{ margin: 0, color: '#d98b84', fontSize: '0.85rem' }}>{error}</p>
-      ) : (
+      )}
+      {!loading && !error && (
         <div className="wiki-history">
           <ul className="wiki-history-list">
             {revisions.map((r, i) => (
@@ -122,11 +122,16 @@ export default function WikiHistory({ slug, onClose, onRestored }) {
                   {parts.length === 0 || (parts.length === 1 && !parts[0].added && !parts[0].removed) ? (
                     <span className="muted">No textual differences.</span>
                   ) : (
-                    parts.map((p, i) => (
-                      <span key={i} className={p.added ? 'diff-add' : p.removed ? 'diff-del' : ''}>
-                        {p.value}
-                      </span>
-                    ))
+                    parts.map((p, i) => {
+                      let cls = ''
+                      if (p.added) cls = 'diff-add'
+                      else if (p.removed) cls = 'diff-del'
+                      return (
+                        <span key={`${i}:${p.value}`} className={cls}>
+                          {p.value}
+                        </span>
+                      )
+                    })
                   )}
                 </div>
               </>