2026-08-31 (ps5_mode runbook) - documented end-to-end steps to enter native PS5 mode

Added comprehensive operational documentation and runbook for entering native PS5 mode (payload/ps5-native / ps5_mode):

• docs/INJECTOR.md: Documented Section 6 ("How to Use: Getting into Native PS5 Mode (ps5_mode)"), including pre-flight checklist, running a native title in the foreground, triggering ./bin/obscene inject, kernel R/W privilege elevation mechanics, and verifying OBS|context|payload/ps5-native.
• docs/HARDWARE.md: Documented cross-reference from the ps4_game ABI restriction to the injector runbook.