[Config] Exposed sensitive files

[emmanuelgautier]

Description

Probe for common sensitive files and debug interfaces left reachable in production.

Checks to implement

• .env, .git, .DS_Store reachable
• Spring Boot actuator endpoints open
• Swagger UI / OpenAPI spec exposed
• .well-known/jwks.json public
• Backup and temp files (.bak, ~)

Tier rationale

Static path probing, no session state required.