aa831968ea
Add two bench empirical verification probes for the whole-volume stale view investigation: 1. Write-commit readback probe in dhara_nand_prog(): after a successful program, immediately read back the same physical page and compare byte-by-byte. Log ECC errors and data mismatches with a counter. 2. Map state logging in ftl_flush_cache(): after each successful dhara_map_write, log the journal root/head/tail/epoch/count to correlate with bench stale-view events. Both probes are marked as bench-only and should be removed before production release.