🎉 Add interfaces

go.mod

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+module codeberg.org/danjones000/responsable-errors
+
+go 1.21.5

interface.go

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+package errors
+
+// ResponsableError is an error that has information useful in an HTTP response.
+// The string returned by Error should be suitable for logging useful information
+// to assist debugging the error.
+// Status should return an appropriate HTTP status.
+// Msg should return a message suitable to display to the end user. If the message
+// returned by Error is safe for the end user, it may simply call that.
+type ResponsableError interface {
+	Error() string
+	Status() int
+	Msg() string
+}
+
+// UnwrappableError allows a ResponsableError to wrap another error.
+// It may be appropriate for Error() to delegate to the wrapped error.
+type UnwrappableError interface {
+	ResponsableError
+	Unwrap() error
+}
+
+// UnwrappableErrorrs allows a ResponsableError to wrap multiple errors.
+// It may be appropriate for Error() to either delegate to the first error,
+// the last error, or to concatenate the return values of all wrapped errors,
+// similar to errors returned by errors.Join
+type UnwrappableErrors interface {
+	ResponsableError
+	Unwrap() []error
+}