At initfs time, /var/log/ doesn't exist (rootfs not yet mounted).
Changed persistent_log from File to Option<File> with .ok() instead
of .unwrap_or_else(|| panic!()). If the file can't be opened, logging
continues without persistence — no crash.
QEMU verification: system boots through initfs→rootfs→switch_root→userland.
Colored init output visible. 25+ services start successfully.
logd now writes all log output to /var/log/system.log (5MB auto-rotation)
in addition to existing scheme listeners. Falls back to /tmp/logd-fallback.log
if /var/log is unavailable. Logs survive reboots for post-mortem analysis.
Part of Phase A2 (Boot Reliability) from BOOT-PROCESS-AUDIT-2026-05-03.
vasilito