Refactor handling of structures and remove endpoints for structures to approve, cancel, reject.
Process of structure entry proposed to be created, updated, deleted by user and
processed (approved, rejected) by administrator or cancelled by user is no more.
Instead, administrator is to create, update, delete structure entry.

Note that commit is first step in removing status as query parameter.

Refactor to reduce complexity and have uniform handling of enums.

Declarations should use Java collection interfaces such as "List" rather than specific implementation classes such as "LinkedList"
Empty statements should be removed
JUnit assertTrue/assertFalse should be simplified to the corresponding dedicated assertion
JUnit5 test classes and methods should have default package visibility
Methods and field names should not be the same or differ only by capitalization
Nested "enum"s should not be declared static

Correct docker integration tests for structures for delete approve.
Refactor docker integration tests.

Updated validation of mnemonic rules for structures and added docker integration tests for REST API endpoints for structures