Complete atomic migration to structured data architecture

Implements clean structured data collection eliminating all string metric
parsing bugs. Collectors now populate AgentData directly with type-safe
field access.

Key improvements:
- Mount points preserved correctly (/ and /boot instead of root/boot)
- Tmpfs discovery added to memory collector
- Temperature data flows as typed f32 fields
- Zero string parsing overhead
- Complete removal of MetricCollectionManager bridge
- Direct ZMQ transmission of structured JSON

All functionality maintained: service tracking, notifications, status
evaluation, and multi-host monitoring.

Cargo.lock

@@ -279,7 +279,7 @@ checksum = "a1d728cc89cf3aee9ff92b05e62b19ee65a02b5702cff7d5a377e32c6ae29d8d"
 
 [[package]]
 name = "cm-dashboard"
-version = "0.1.137"
+version = "0.1.138"
 dependencies = [
  "anyhow",
  "chrono",
@@ -301,7 +301,7 @@ dependencies = [
 
 [[package]]
 name = "cm-dashboard-agent"
-version = "0.1.137"
+version = "0.1.138"
 dependencies = [
  "anyhow",
  "async-trait",
@@ -324,7 +324,7 @@ dependencies = [
 
 [[package]]
 name = "cm-dashboard-shared"
-version = "0.1.137"
+version = "0.1.138"
 dependencies = [
  "chrono",
  "serde",