Minor fmt and doc changes

- use `DateTime` `Display` instead of `Debug` in `ParseTimestampError`
  `Display`
- comments should go above `#[cfg(feature)]`
- adds random comments

Author: allan2

crates/devolutions-pedm/src/api/err.rs

@@ -6,6 +6,8 @@ use hyper::StatusCode;
 use crate::db::DbError;
 
 /// An error type for route handlers.
+/// 
+/// The error contains a status code and an optional error message.
 #[derive(Debug)]
 pub(crate) struct HandlerError(StatusCode, Option<String>);
 

crates/devolutions-pedm/src/db/err.rs

@@ -20,6 +20,7 @@ pub enum DbError {
     /// For example, we may have a value that is `i16` in the data model but it is stored as `i64` in libSQL.
     #[cfg(feature = "libsql")]
     TryFromInt(TryFromIntError),
+    /// An error that occurs when parsing microseconds since epoch into `chrono::DateTime<Utc>`.
     #[cfg(feature = "libsql")]
     Timestamp(ParseTimestampError),
     #[cfg(feature = "postgres")]
@@ -106,8 +107,8 @@ impl DbError {
     }
 }
 
-#[cfg(feature = "libsql")]
 /// A custom error type equivalent for `chrono::LocalResult`.
+#[cfg(feature = "libsql")]
 #[derive(Debug)]
 pub enum ParseTimestampError {
     None,
@@ -127,7 +128,7 @@ impl fmt::Display for ParseTimestampError {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
             Self::None => write!(f, "no timestamp found"),
-            Self::Ambiguous(dt1, dt2) => write!(f, "ambiguous timestamp: {dt1:?} or {dt2:?}"),
+            Self::Ambiguous(dt1, dt2) => write!(f, "ambiguous timestamp: {dt1} or {dt2}"),
         }
     }
 }