Add Technical Kiwi website with Go, templ, and HTMX.

Single-page site with gallery by album and event, contact form over SMTP,
Docker dev/prod setup, and on-server image derivatives. Gallery photos stay
local (app/images/ is gitignored).

Co-authored-by: Cursor <cursoragent@cursor.com>

app/internal/mail/send.go

@@ -0,0 +1,163 @@
+package mail
+
+import (
+	"bytes"
+	"crypto/tls"
+	"fmt"
+	"net"
+	"net/smtp"
+	"strings"
+)
+
+// ContactEmail sends a contact form message via the configured SMTP relay.
+func (c Config) ContactEmail(name, replyTo, message string) error {
+	subject := fmt.Sprintf("Contact form: %s", name)
+	var body bytes.Buffer
+	body.WriteString(fmt.Sprintf("Name: %s\n", name))
+	body.WriteString(fmt.Sprintf("Email: %s\n\n", replyTo))
+	body.WriteString(message)
+
+	return c.send(subject, body.String(), replyTo)
+}
+
+func (c Config) send(subject, body, replyTo string) error {
+	addr := fmt.Sprintf("%s:%d", c.Host, c.Port)
+
+	var msg bytes.Buffer
+	msg.WriteString(fmt.Sprintf("From: %s\r\n", c.From))
+	msg.WriteString(fmt.Sprintf("To: %s\r\n", c.To))
+	if replyTo != "" {
+		msg.WriteString(fmt.Sprintf("Reply-To: %s\r\n", replyTo))
+	}
+	msg.WriteString(fmt.Sprintf("Subject: %s\r\n", subject))
+	msg.WriteString("MIME-Version: 1.0\r\n")
+	msg.WriteString("Content-Type: text/plain; charset=UTF-8\r\n")
+	msg.WriteString("\r\n")
+	msg.WriteString(body)
+
+	raw := msg.Bytes()
+	from := extractAddr(c.From)
+
+	var auth smtp.Auth
+	if c.User != "" {
+		auth = smtp.PlainAuth("", c.User, c.Password, c.Host)
+	}
+
+	switch c.tlsMode() {
+	case "plain":
+		return smtp.SendMail(addr, auth, from, []string{c.To}, raw)
+	case "tls":
+		return c.sendTLS(addr, auth, from, raw)
+	default:
+		return c.sendStartTLS(addr, auth, from, raw)
+	}
+}
+
+func (c Config) tlsMode() string {
+	switch strings.ToLower(c.TLS) {
+	case "plain", "tls":
+		return strings.ToLower(c.TLS)
+	}
+	if c.Port == 465 {
+		return "tls"
+	}
+	if c.Port == 25 {
+		return "plain"
+	}
+	return "starttls"
+}
+
+func (c Config) sendStartTLS(addr string, auth smtp.Auth, from string, raw []byte) error {
+	conn, err := net.Dial("tcp", addr)
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	client, err := smtp.NewClient(conn, c.Host)
+	if err != nil {
+		return err
+	}
+	defer client.Close()
+
+	if ok, _ := client.Extension("STARTTLS"); ok {
+		if err := client.StartTLS(&tls.Config{ServerName: c.Host}); err != nil {
+			return err
+		}
+	}
+
+	if auth != nil {
+		if ok, _ := client.Extension("AUTH"); ok {
+			if err := client.Auth(auth); err != nil {
+				return err
+			}
+		}
+	}
+
+	if err := client.Mail(from); err != nil {
+		return err
+	}
+	if err := client.Rcpt(c.To); err != nil {
+		return err
+	}
+	w, err := client.Data()
+	if err != nil {
+		return err
+	}
+	if _, err := w.Write(raw); err != nil {
+		return err
+	}
+	if err := w.Close(); err != nil {
+		return err
+	}
+	return client.Quit()
+}
+
+func (c Config) sendTLS(addr string, auth smtp.Auth, from string, raw []byte) error {
+	conn, err := tls.Dial("tcp", addr, &tls.Config{ServerName: c.Host})
+	if err != nil {
+		return err
+	}
+	defer conn.Close()
+
+	client, err := smtp.NewClient(conn, c.Host)
+	if err != nil {
+		return err
+	}
+	defer client.Close()
+
+	if auth != nil {
+		if ok, _ := client.Extension("AUTH"); ok {
+			if err := client.Auth(auth); err != nil {
+				return err
+			}
+		}
+	}
+
+	if err := client.Mail(from); err != nil {
+		return err
+	}
+	if err := client.Rcpt(c.To); err != nil {
+		return err
+	}
+	w, err := client.Data()
+	if err != nil {
+		return err
+	}
+	if _, err := w.Write(raw); err != nil {
+		return err
+	}
+	if err := w.Close(); err != nil {
+		return err
+	}
+	return client.Quit()
+}
+
+func extractAddr(from string) string {
+	if i := strings.Index(from, "<"); i >= 0 {
+		if j := strings.Index(from[i:], ">"); j > 0 {
+			return strings.TrimSpace(from[i+1 : i+j])
+		}
+	}
+	return strings.TrimSpace(from)
+}