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>

server/src/utils/shardIngest.js

@@ -188,8 +188,10 @@ async function applyStateChange(event, deps) {
 // Ingest one event. Returns { logged, stored } for tests/stats. `fromBackfill`
 // suppresses the SSE broadcast (a reconnect replay shouldn't re-animate the
 // live ticker). Never throws — a bad single event must not kill the feed.
-async function ingest(event, deps = {}) {
-  const d = {
+// Resolve the injectable dependencies to their live defaults (tests override a
+// subset). Split out so ingest() isn't penalised for the fan of `|| default`s.
+function resolveDeps(deps) {
+  return {
     shardEvents: deps.shardEvents || shardEventsModel,
     shardState: deps.shardState || shardStateModel,
     shardLinks: deps.shardLinks || shardLinksModel,
@@ -198,6 +200,10 @@ async function ingest(event, deps = {}) {
     pushDispatch: deps.pushDispatch || pushDispatch.fromShardEvent,
     log: deps.log || defaultLog,
   }
+}
+
+async function ingest(event, deps = {}) {
+  const d = resolveDeps(deps)
 
   if (!event || typeof event.kind !== 'string') return { logged: false, stored: false }
   // ws.hello / pong are transport frames, not game events.