fix(server): return read item errors for invalid ranges

[gijzelaerr]

Summary:

• return 0x0A for reads from unregistered server areas
• return 0x05 for reads outside or crossing registered memory
• preserve item-level errors for single and multi-item reads
• add integration regressions and a changelog entry

Validation:

• 2089 passed, 82 skipped
• pre-commit passed
• source distribution and wheel built successfully

Closes #894.

Generated with Codex.