feat: replace Bootstrap with custom CSS and add profile page

- Add self-hosted style.css replacing Bootstrap CDN dependency
- Add profile.html with tabbed view (account info, emails/aliases, API token)
- Refactor login handler to pass structured data to template instead of building HTML strings
- Add brand-name and brand-logo flags/env vars for UI customization
- Update CSP to allow brand logo domain and remove CDN references
- Update all templates to pass template vars to header/footer and use new CSS classes

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

main.go

@@ -19,6 +19,8 @@ import (
 
 var myPublicURL = "https://ldap.nemunai.re"
 var devMode bool
+var brandName = "chldapasswd"
+var brandLogo = ""
 
 // dockerRegistrySecret is required for X-Special-Auth anonymous access.
 // If empty, the feature is disabled.
@@ -82,10 +84,20 @@ func main() {
 	var configfile = flag.String("config", "", "path to the configuration file")
 	var publicURL = flag.String("public-url", myPublicURL, "Public base URL used in password reset emails")
 	var dev = flag.Bool("dev", false, "Development mode: disables HSTS and cookie Secure flag for local HTTP testing")
+	var bname = flag.String("brand-name", "chldapasswd", "Brand name displayed in the UI")
+	var blogo = flag.String("brand-logo", "", "URL of brand logo displayed in the UI (added to CSP img-src)")
 	flag.Parse()
 
 	myPublicURL = *publicURL
 	devMode = *dev
+	brandName = *bname
+	brandLogo = *blogo
+	if val, ok := os.LookupEnv("BRAND_NAME"); ok {
+		brandName = val
+	}
+	if val, ok := os.LookupEnv("BRAND_LOGO"); ok {
+		brandLogo = val
+	}
 	if devMode {
 		log.Println("WARNING: running in development mode — security features relaxed, do not use in production")
 	}
@@ -220,6 +232,7 @@ func main() {
 
 	// Register handlers
 	http.HandleFunc(fmt.Sprintf("GET %s/altcha.min.js", *baseURL), serveAltchaJS)
+	http.HandleFunc(fmt.Sprintf("GET %s/style.css", *baseURL), serveStyleCSS)
 	http.HandleFunc(fmt.Sprintf("GET %s/altcha-challenge", *baseURL), serveAltchaChallenge)
 	http.HandleFunc(fmt.Sprintf("%s/{$}", *baseURL), changePassword)
 	http.HandleFunc(fmt.Sprintf("POST %s/api/v1/aliases", *baseURL), addyAliasAPI)