Centralise the NIP-05 wildcard check (name != "_") on the data class itself.

quartz/src/commonMain/kotlin/com/vitorpamplona/quartz/nip05DnsIdentifiers/Nip05Id.kt

@@ -36,6 +36,12 @@ data class Nip05Id(
      */
     fun toDisplayValue(): String = if (name == "_") domain else assemble(name, domain)
 
+    /**
+     * False when [name] is the NIP-05 wildcard `"_"`; use to gate rendering of
+     * the local part when name and domain are shown as separate widgets.
+     */
+    fun hasLocalPart(): Boolean = name != "_"
+
     fun toUserUrl(): String = userUrl(name, domain)
 
     fun toDomainUrl(): String = domainUrl(domain)

quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/nip05DnsIdentifiers/Nip05Test.kt

@@ -123,6 +123,20 @@ class Nip05Test {
         assertEquals("example.com", nip05.toDisplayValue())
     }
 
+    @Test
+    fun `hasLocalPart is true for regular name`() {
+        val nip05 = Nip05Id.parse("alice@example.com")
+        assertNotNull(nip05)
+        assertEquals(true, nip05.hasLocalPart())
+    }
+
+    @Test
+    fun `hasLocalPart is false for underscore name`() {
+        val nip05 = Nip05Id.parse("_@example.com")
+        assertNotNull(nip05)
+        assertEquals(false, nip05.hasLocalPart())
+    }
+
     @Test
     fun `test json parsing with relays`() {
         val parsedNip05 = Nip05Id.parse("bob@test.com")