Convert explicitly between Unicode and Zawgyi

The source encoding must be supplied; the direction is never chosen automatically. Set validateSource=true for a conservative preflight. Direction-changing requests return 400 encoding_mixed for mixed evidence, encoding_mismatch for evidence contrary to from, or encoding_uncertain for any unknown Myanmar segment. No partial output is returned. Equal directions remain exact no-ops. Detection can miss encoding switches inside a run and does not prove linguistic correctness. Omission/false preserves unchecked conversion.

curl -X POST "https://example.com/text/convert" \  -H "Content-Type: application/json" \  -d '{    "text": "string",    "from": "unicode",    "to": "unicode"  }'

{  "input": "string",  "output": "string",  "from": "unicode",  "to": "unicode",  "changed": true,  "profile": "cldr-zawgyi-v1"}