Made certain config options editable in the app config.

Documentation.en.md

@@ -145,6 +145,25 @@ File: `src\HostAvailabilityMonitor\appsettings.json`
 - `HipVirtualMachines`: optional static VM checks
 - `Targets`: endpoints to probe
 
+### Runtime section
+
+Important fields in `Runtime`:
+
+- `MaxConcurrency`: maximum number of parallel endpoint checks
+- `DefaultValidateUncPathAccess`: default for UNC targets without their own `ValidateUncPathAccess` value
+- `NonZeroExitCodeOnAnyFailure`: exit with code `2` when endpoint failures are found
+- `NonZeroExitCodeOnExecutionError`: exit with code `1` on technical execution errors
+- `StateDirectory`: directory for the state file
+- `StateFileName`: state file name, default `monitor-state.json`
+
+### Logging section
+
+Important fields in `Logging`:
+
+- `LogDirectory`: directory for rolling log files
+- `FilePrefix`: prefix for daily log files
+- `RetentionDays`: number of daily log files to retain, default `30`; `0` disables automatic cleanup
+
 ### Email section
 
 Important fields in `Email`:
@@ -330,12 +349,13 @@ It contains:
 - `Logging`
 - `EventLog`
 - `Email`
+- `HipVirtualMachines`
 
 `Targets` is rebuilt by the generator at runtime.
 
 Important:
 
-When the generator writes the monitor JSON, the daily summary options and static HIP VM settings are also copied into the generated target file. That means `GeneratedMonitorConfig.Email.SendDailySummary`, `DailySummaryHourLocal`, `DailySummaryMinuteLocal`, and `GeneratedMonitorConfig.HipVirtualMachines` flow directly into the output monitor configuration.
+When the generator writes the monitor JSON, runtime, logging, daily summary, and static HIP VM settings are also copied into the generated target file. That means values such as `GeneratedMonitorConfig.Runtime.StateFileName`, `GeneratedMonitorConfig.Logging.RetentionDays`, `GeneratedMonitorConfig.Email.SendDailySummary`, `DailySummaryHourLocal`, `DailySummaryMinuteLocal`, and `GeneratedMonitorConfig.HipVirtualMachines` flow directly into the output monitor configuration.
 
 ---
 
@@ -472,7 +492,7 @@ The generator is designed defensively:
 The monitor is also defensive:
 
 - daily rolling logs
-- default retention of 5 days
+- default retention of 30 days, configurable through `Logging.RetentionDays`
 - event log writes are best effort only
 - state file is written atomically
 - failure/recovery emails follow explicit notification rules