Add scripts and configuration files for mergerfs setup and testing

- Created backup files for wipefs on specific disk partitions.
- Added db-test script to verify metadata.db file integrity.
- Documented successful mergerfs branch and pool configurations in mfs-good.txt.
- Implemented mfs write test in mfs-test.txt.
- Included mergerfs version and device information in mfs.txt.
- Developed rebuild scripts for mergerfs stages, including verification and filesystem creation.
- Generated stage logs for each rebuild step to track disk and filesystem status.
- Added checks for systemd mount requirements and filesystem verification in stage4.

post-rebuild/rebuild-stage4

@@ -0,0 +1,24 @@
+findmnt --verify --verbose
+
+systemctl daemon-reload
+mount -a
+
+echo
+echo '=== BRANCHES ==='
+findmnt /mnt/banshee/4tb
+findmnt /mnt/banshee/8a
+findmnt /mnt/banshee/8b
+findmnt /mnt/banshee/6tb
+
+echo
+echo '=== POOL ==='
+findmnt /storage
+
+echo
+df -hT \
+  /mnt/banshee/4tb \
+  /mnt/banshee/8a \
+  /mnt/banshee/8b \
+  /mnt/banshee/6tb \
+  /storage
+