wapp: emit event.2 event when recovering panic (#47)

Fixes #46

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wlog/wapp/fatal.go

@@ -20,6 +20,7 @@ import (
 
 	"github.com/palantir/witchcraft-go-error"
 	"github.com/palantir/witchcraft-go-logging/wlog/diaglog/diag1log"
+	"github.com/palantir/witchcraft-go-logging/wlog/evtlog/evt2log"
 	"github.com/palantir/witchcraft-go-logging/wlog/svclog/svc1log"
 )
 
@@ -50,6 +51,11 @@ func RunWithFatalLogging(ctx context.Context, runFn func(ctx context.Context) er
 					werror.UnsafeParam("recovered", r))
 			}
 		}
+		if evtlog := evt2log.FromContext(ctx); evtlog != nil {
+			evtlog.Event("wapp.panic_recovered",
+				evt2log.Value("stacktrace", stacktrace),
+				evt2log.UnsafeParam("recovered", r))
+		}
 	}()
 	if err := runFn(ctx); err != nil {
 		svc1log.FromContext(ctx).Error("error", svc1log.Stacktrace(err))