Fix bug: fix the error when VRChat log file does not exist

If Outvoke was started with no VRChat log file present and then
VRChat was started with Outvoke still running, Outvoke could
terminate with an error.

This has been fixed.

how to repro:

---------------
1. While VRChat is not running, delete all VRChat log files

2. launch Outvoke as follows:

$ ./outvoke.rb -e 'hook "vrchat-001", /pickup/i'

3. start VRChat
---------------

outvoke.rb

 #!/usr/bin/env ruby
 #
 # ==========================================================================
-# Outvoke -- version 0.0.99.20241112
+# Outvoke -- version 0.0.99.20241112.1
 #
 # written by cleemy desu wayo / Licensed under CC0 1.0
 #
@@ -25,7 +25,7 @@ class Outvoke
 
     @version = Struct.new(:branch, :body).new(
       '0.1',
-      '0.0.99.20241112'
+      '0.0.99.20241112.1'
     )
 
     @ds      = Hash.new
@@ -562,6 +562,7 @@ class OutvokeDataSourceVrchat < OutvokeDataSource
     @status.file_size = 0
     @status.count = 0
     @status.lineno = 0
+    @status.last_joined_time = Time.now
     @log_dir = ''
     @is_first_time_log_check = true
     @has_new_log_lines = false
@@ -605,12 +606,14 @@ class OutvokeDataSourceVrchat < OutvokeDataSource
   end
 
   def before_each_event
+    tmp_now = Time.now
+
     Dir.glob("#{@log_dir}/output_log_*.txt").last.then do
       if _1 != @status.logfile
         @status.logfile = _1
         @status.lineno = 0
         if not $outvoke.quiet_mode?    # TODO
-          puts "[#{Time.now}] [outvoke-system] #{@label}: a new log file was found." if @status.logfile
+          puts "[#{tmp_now}] [outvoke-system] #{@label}: a new log file was found." if @status.logfile
         end
       end
     end
@@ -618,7 +621,7 @@ class OutvokeDataSourceVrchat < OutvokeDataSource
     # return if not found
     unless @status.logfile
       if @is_first_time_log_check
-        puts "[#{Time.now}] [outvoke-system] #{@label}: ERROR: VRChat log file not found"
+        puts "[#{tmp_now}] [outvoke-system] #{@label}: ERROR: VRChat log file not found"
       end
       return
     end