address PR review: stricter HTML detection and fence label punctuation

frontend/apps/main/src/features/conversation/ReplyBox.vue

@@ -223,7 +223,8 @@ const runAiGeneration = async (requestFn) => {
     if (uuid !== currentConversationUUID.value) return
     const out = resp.data.data || ''
     // A model can ignore the HTML-output instruction; plain text pasted into the editor loses its line breaks.
-    htmlContent.value = /<[a-z][\s\S]*>/i.test(out) ? out : convertTextToHtml(out)
+    // The tag check must not match angle-bracketed plain text like "Contact <user@example.com>".
+    htmlContent.value = /<\/?[a-z][a-z0-9]*(\s[^>]*)?\/?>/i.test(out) ? out : convertTextToHtml(out)
   } catch (error) {
     emitter.emit(EMITTER_EVENTS.SHOW_TOAST, {
       variant: 'destructive',

internal/ai/ai.go

@@ -40,7 +40,7 @@ var (
 	//go:embed queries.sql
 	efs embed.FS
 
-	codeFenceOpenRe = regexp.MustCompile("^```[a-zA-Z0-9]*$")
+	codeFenceOpenRe = regexp.MustCompile("^```[a-zA-Z0-9+#./_-]*$")
 
 	ErrInvalidAPIKey       = errors.New("invalid API Key")
 	ErrApiKeyNotSet        = errors.New("api Key not set")

internal/ai/ai_test.go

@@ -48,6 +48,16 @@ func TestStripCodeFence(t *testing.T) {
 			in:   "```<p>Hello,</p>\n<p>Thanks.</p>\n```",
 			want: "```<p>Hello,</p>\n<p>Thanks.</p>\n```",
 		},
+		{
+			name: "c++ fence unwrapped",
+			in:   "```c++\nint main() {}\n```",
+			want: "int main() {}",
+		},
+		{
+			name: "text/plain fence unwrapped",
+			in:   "```text/plain\nHello there.\n```",
+			want: "Hello there.",
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {