Fix nginx sub-services persistent caching with complete service data storage

Resolves nginx sites appearing only briefly during collection cycles by implementing proper caching of complete service data including sub-services.

Changes:
- Add cached_service_data field to store complete ServiceData with sub-services
- Modify collection logic to cache full service objects instead of basic ServiceInfo
- Update cache retrieval to use complete cached data preserving nginx site metrics
- Eliminate flickering of nginx sites between collection cycles

Version bump to v0.1.148

Cargo.lock

@@ -279,7 +279,7 @@ checksum = "a1d728cc89cf3aee9ff92b05e62b19ee65a02b5702cff7d5a377e32c6ae29d8d"
 
 [[package]]
 name = "cm-dashboard"
-version = "0.1.146"
+version = "0.1.147"
 dependencies = [
  "anyhow",
  "chrono",
@@ -301,7 +301,7 @@ dependencies = [
 
 [[package]]
 name = "cm-dashboard-agent"
-version = "0.1.146"
+version = "0.1.147"
 dependencies = [
  "anyhow",
  "async-trait",
@@ -324,7 +324,7 @@ dependencies = [
 
 [[package]]
 name = "cm-dashboard-shared"
-version = "0.1.146"
+version = "0.1.147"
 dependencies = [
  "chrono",
  "serde",