Investigate and document operation ordering requirements

### Context & versions
cardano-rosetta-java 1.3.x - Construction API

### Problem
The documentation states operations must be ordered (inputs/outputs → certificates → withdrawals), but it's unclear if the Java implementation actually enforces this or just follows it by (old ts implementation) convention.

### Steps to reproduce
1. Call `/construction/payloads` with operations in different orders
2. Test if transaction construction succeeds with reordered operations

### Investigation needed
- [ ] Test if rosetta-java accepts operations in different orders
- [ ] Verify if reordering breaks transaction construction
- [ ] Check if this is a hard requirement or just a convention

### Documentation updates needed
- [ ] If ordering is required: Document as a requirement with clear error messages
- [ ] If ordering is flexible: Update docs to clarify it's a recommendation
- [ ] Add examples showing valid operation orderings