refactor: remove minimum required fields constructor from ApplicationInformationDto (#43)

Removed the 4-parameter convenience constructor. DTO now has only:
  1. Default no-arg constructor (required for JAXB)
  2. Canonical constructor with all 37 fields (auto-generated by record)

  All 18 integration tests passing (H2, MySQL, PostgreSQL).

  Resolves #40

Author: dfcoffin

openespi-common/src/main/java/org/greenbuttonalliance/espi/common/dto/usage/ApplicationInformationDto.java

@@ -202,6 +202,8 @@ public record ApplicationInformationDto(
 
     /**
      * Default constructor for JAXB.
+     * Creates an ApplicationInformationDto with all fields set to null.
+     * The canonical constructor with all fields is automatically provided by the record declaration.
      */
     public ApplicationInformationDto() {
         this(null, null, null, null, null, null, null, null, null,
@@ -211,17 +213,6 @@ public ApplicationInformationDto() {
              null);
     }
 
-    /**
-     * Constructor for basic application information (minimum required fields).
-     */
-    public ApplicationInformationDto(String dataCustodianId, String clientId, String clientSecret, String clientName) {
-        this(null, dataCustodianId, null, null, null, null, null, null, null,
-             null, null, null, null, null, null, null, null, null,
-             clientSecret, null, clientName, null, null, clientId, null, null,
-             null, null, null, null, null, null, null, null, null,
-             null, null);
-    }
-
     // JAXB property accessors - must match propOrder sequence
 
     @XmlElement(name = "dataCustodianId", namespace = "http://naesb.org/espi")