Enforce Unique Session IDs (TR-03130 §3.3.1)

[Hermann-Core]

Ensure each TC Token issued corresponds to a unique session identifier that is both hard to guess and never reused.

Tasks

• Enforce uniqueness at the DB/session store level
• Reject duplicate session_id reuse
• Add test cases for collision resistance

Reference

• TR-03130 Part 1, §3.3.1

[ndefokou]

PR: ADORSYS-GIS/eID-Server#41