Docs: Add advanced cryptography pentest tasks #15

Description

Expand docs/PENTEST_TASKS_ADVANCED.md with a dedicated Cryptography / Key Management / Protocol Misuse section.

The current advanced task set covers authentication, authorization, injection, OAuth/JWT, supply chain, cloud, and other major security domains, but does not have a dedicated section for applied cryptographic vulnerabilities.

Add advanced tasks covering areas such as:

• Cryptographic randomness and nonce/IV reuse
• AEAD and unauthenticated encryption misuse
• Password hashing and KDF weaknesses
• RSA and signature verification misuse
• Key generation, storage, rotation, and trust boundaries
• ECDSA/DSA nonce failures
• DH/ECDH public-value validation
• Key/domain separation
• TLS and certificate verification
• Custom cryptographic composition and protocol misuse

Tasks should follow the existing staff-level format: trace the implementation, establish exploitability, and prove concrete security impact rather than simply flagging use of a primitive or algorithm.

Proposed changes

• Add a new Cryptography / key management / protocol misuse section with tasks 101–115.
• Rename the document heading from 100 Advanced / Staff-Level Pentest Tasks to Advanced / Staff-Level Pentest Tasks so the task set can continue growing.