Capture exceptions when walkthrough scanner stops unexpectedly (#128)

Catch errors that happen during the walkthrough scanner to reduce noise,
especially when the game is closed unexpectedly. Cleans up the console
and logs when the player closes the game.

app/clarity.py

@@ -1,4 +1,5 @@
 from common.db_ops import sql_read, sql_write
+from common.errors import MemoryReadError
 from common.lib import (
     get_project_root,
     is_dqx_process_running,
@@ -17,6 +18,7 @@
     walkthrough_pattern,
 )
 from common.translate import convert_into_eng, detect_lang, Translate
+from pymem.exception import WinAPIError
 
 import re
 import sys
@@ -232,12 +234,21 @@ def loop_scan_for_walkthrough():
                             time.sleep(1)
             else:
                 time.sleep(1)
+    except WinAPIError as e:
+        if e.error_code == 299: # usually means the user closed the game.
+            if not is_dqx_process_running():
+                sys.exit(0)
+            raise(e)
+    except MemoryReadError as e:
+        if not is_dqx_process_running():
+            sys.exit(0)
+        raise(e)
     except Exception:
         if not is_dqx_process_running():
-            log.exception("A problem with the walkthrough scanner was detected.")
-            sys.exit(1)
+            sys.exit(0)
         else:
-            log.exception("Problem detected running walkthrough scanner.")
+            log.exception("Problem was detected with the walkthrough scanner.")
+            sys.exit(1)
 
 
 def run_scans(player_names=True, npc_names=True):