Improve NVMe serial parsing and restructure MergerFS display

- Fix NVMe serial number parsing to handle whitespace variations
- Move mount point to MergerFS header, remove drive count
- Restructure data drives to same level as parity with Data_1, Data_2 labels
- Remove "Total:" label from pool usage line
- Update parity to use closing tree symbol as last item

Cargo.lock

@@ -279,7 +279,7 @@ checksum = "a1d728cc89cf3aee9ff92b05e62b19ee65a02b5702cff7d5a377e32c6ae29d8d"
 
 [[package]]
 name = "cm-dashboard"
-version = "0.1.155"
+version = "0.1.156"
 dependencies = [
  "anyhow",
  "chrono",
@@ -301,7 +301,7 @@ dependencies = [
 
 [[package]]
 name = "cm-dashboard-agent"
-version = "0.1.155"
+version = "0.1.156"
 dependencies = [
  "anyhow",
  "async-trait",
@@ -324,7 +324,7 @@ dependencies = [
 
 [[package]]
 name = "cm-dashboard-shared"
-version = "0.1.155"
+version = "0.1.156"
 dependencies = [
  "chrono",
  "serde",