DatabaseConfig __repr__ leaks partial password material

[Mo33n]

Confirmation

• I’ve re-read the relevant sections of the documentation.
• I’ve searched existing issues and discussions to avoid duplicates.
• I’ve reviewed or skimmed the source code (or examples) to confirm the behavior is not by design.
• I’ve tested this issue using a recent development wheel and can still reproduce it.

Expected Behavior

Secret fields in repr output should be fully redacted.

Actual Behavior

DatabaseConfig repr exposes first/last characters of password and full short passwords.

Steps to Reproduce the Problem

1. Create DatabaseConfig(password="SuperSecret123") and print/repr it.
2. Observe partial leak (e.g., Su...23).
3. Repeat with short password and observe full leak.

Code Snippets or Logs

File: nautilus_trader/common/config.py
Method: DatabaseConfig.repr

Specifications

• OS platform: macOS (darwin 24.6.0)
• Python version: 3.12
• nautilus_trader version: source checkout (develop)