chore: prettier format all files, brotli, Sentry release tagging, CI gates

Prettier: auto-formatted 103 files to fix baseline. Prettier check in CI
  is now a hard gate (removed continue-on-error).

Brotli: installed libnginx-mod-http-brotli-filter/static. Enabled in nginx
  with brotli_static on for pre-compressed assets and comp_level 6.

Sentry releases: deploy script now exports VITE_APP_VERSION=<git-short-sha>
  before building so each Sentry release maps to an exact commit.
  CI also passes github.sha as VITE_APP_VERSION.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/util/colorMXID.js

@@ -10,7 +10,7 @@ function hashCode(str) {
   for (i = 0; i < str.length; i += 1) {
     chr = str.charCodeAt(i);
     // eslint-disable-next-line no-bitwise
-    hash = ((hash << 5) - hash) + chr;
+    hash = (hash << 5) - hash + chr;
     // eslint-disable-next-line no-bitwise
     hash |= 0;
   }