Improve notification behavior during startup and recovery

Fix notification issues for better operational experience:

Startup Notification Suppression:
- Suppress notifications for transitions from Status::Unknown during agent/server startup
- Prevents notification spam when services transition from Unknown to Warning/Critical on restart
- Only real status changes (not initial discovery) trigger notifications
- Maintains alerting for actual service state changes after startup

Recovery Notification Refinement:
- Recovery notifications only sent when ALL services reach OK status
- Individual service recoveries suppressed if other services still have problems
- Ensures recovery notifications indicate complete system health restoration
- Prevents premature celebration when partial recoveries occur

Result: Clean startup experience without false alerts and meaningful recovery
notifications that truly indicate full system health restoration.

Bump version to v0.1.48

Cargo.lock

@@ -270,7 +270,7 @@ checksum = "a1d728cc89cf3aee9ff92b05e62b19ee65a02b5702cff7d5a377e32c6ae29d8d"
 
 [[package]]
 name = "cm-dashboard"
-version = "0.1.46"
+version = "0.1.47"
 dependencies = [
  "anyhow",
  "chrono",
@@ -291,7 +291,7 @@ dependencies = [
 
 [[package]]
 name = "cm-dashboard-agent"
-version = "0.1.46"
+version = "0.1.47"
 dependencies = [
  "anyhow",
  "async-trait",
@@ -314,7 +314,7 @@ dependencies = [
 
 [[package]]
 name = "cm-dashboard-shared"
-version = "0.1.46"
+version = "0.1.47"
 dependencies = [
  "chrono",
  "serde",