Bump version to 0.10.0

Substantial scope since 0.9.0: API keys for forward auth, SecurityMailer
alerts on 8 account-security events, dark mode, Remember-me with proper
browser-session cookie semantics, SvgScrubber for icon XSS, OIDC
auth-code replay revocation, forward-auth caching + rate limiting, and
fixes for broken invitation / password-reset emails.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

config/initializers/version.rb

@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module Clinch
-  VERSION = "0.9.0"
+  VERSION = "0.10.0"
 end