feat: add serializable data models with FlexibleStringSerializer for number coercion

composeApp/src/commonMain/kotlin/ch/parano/myice/models/EventDetail.kt

@@ -0,0 +1,14 @@
+package ch.parano.myice.models
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class EventDetail(
+    val title: String = "",
+    val type: String = "",
+    val place: String = "",
+    @SerialName("time_start") val timeStart: String = "",
+    @SerialName("time_end") val timeEnd: String = "",
+    val convocation: Convocation = Convocation(),
+)