Log partial email body read errors instead of silently ignoring

io.ReadAll errors are unlikely for short yes/no replies but worth
logging for diagnosability. Processing continues with whatever bytes
were read to remain resilient.

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

pkg/email/fetch.go

@@ -3,6 +3,7 @@ package email
 import (
 	"fmt"
 	"io"
+	"log"
 	"net/mail"
 	"strings"
 
@@ -92,6 +93,9 @@ func fetchEmails(imapClient *client.Client) ([]Email, error) {
 				return result, err
 			}
 			body, err := io.ReadAll(m.Body)
+			if err != nil {
+				log.Printf("Warning: partial read of email body from %s: %s", fromAddress, err)
+			}
 
 			email := NewEmail(
 				[]string{toAddress},