various: add Display impls for domain enums; improve contextual errors

Signed-off-by: NotAShelf <raf@notashelf.dev>
Change-Id: Ia16e7e34cda6ae3e12590ea1ea9268486a6a6964

crates/pinakes-core/src/model.rs

@@ -181,6 +181,23 @@ pub enum CustomFieldType {
   Boolean,
 }
 
+impl CustomFieldType {
+  pub fn as_str(&self) -> &'static str {
+    match self {
+      Self::Text => "text",
+      Self::Number => "number",
+      Self::Date => "date",
+      Self::Boolean => "boolean",
+    }
+  }
+}
+
+impl std::fmt::Display for CustomFieldType {
+  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    f.write_str(self.as_str())
+  }
+}
+
 /// A tag that can be applied to media items.
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct Tag {
@@ -210,6 +227,21 @@ pub enum CollectionKind {
   Virtual,
 }
 
+impl CollectionKind {
+  pub fn as_str(&self) -> &'static str {
+    match self {
+      Self::Manual => "manual",
+      Self::Virtual => "virtual",
+    }
+  }
+}
+
+impl std::fmt::Display for CollectionKind {
+  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    f.write_str(self.as_str())
+  }
+}
+
 /// A member of a collection with position tracking.
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct CollectionMember {