Update gems and fix lint to clear CI failures

Bumps dependencies (jwt 3.2.0, puma 8.0.2, net-imap 0.6.4.1 and others
via bundle update) to resolve bundler-audit advisories, and applies
standardrb autofixes so the lint job passes.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

app/helpers/application_helper.rb

@@ -31,7 +31,7 @@ module ApplicationHelper
     end
     lines << "OIDC_DISCOVERY_URL=#{OidcJwtService.issuer_url}"
     lines << "OIDC_PROVIDER_NAME='Clinch'"
-    lines << "OIDC_REQUIRE_PKCE=#{application.requires_pkce? ? 'true' : 'false'}"
+    lines << "OIDC_REQUIRE_PKCE=#{application.requires_pkce? ? "true" : "false"}"
     lines
   end