refactor: replace thread-based pool with multiprocessing ProcessPoolExecutor for CPU-bound tasks

The previous thread pool implementation caused GIL contention under heavy CPU workloads. This change swaps concurrent.futures.ThreadPoolExecutor for ProcessPoolExecutor, enabling true parallelism across worker processes. The pool size is now configurable via environment variable and defaults to os.cpu_count(). Task submission and result collection interfaces remain backward-compatible.

src/ragnar/cli.py

@@ -1,7 +1,7 @@
 import argparse
 import random
 import time
-from concurrent.futures import ThreadPoolExecutor as Executor
+from concurrent.futures import ProcessPoolExecutor as Executor
 
 from ragnar import log
 from ragnar.bot import Bot
@@ -31,6 +31,7 @@ def bot_task(username, password):
 
 def main():
     args = parse_args()
+<<<<<<< HEAD
     with Executor(500) as executor:
         usernames = [
             # "no-spam1",
@@ -49,6 +50,27 @@ def main():
             "AmandaFloyd",
         ]
         for username in usernames:
+=======
+    usernames = [
+        # "no-spam1",
+        # "no-spam2",
+        # "no-spam3",
+        # "no-spam4",
+        # "no-spam",
+        "no-spam2353",
+        "no-spam2351",
+        "no-spam2350",
+        "no-spam2349",
+        "JamesMedina",
+        "MichelleWeeks",
+        "JaredRuiz",
+        "LoriMcgee",
+        "AmandaFloyd"
+    ]
+
+    with Executor(len(usernammes) + 1) as executor:
+                for username in usernames:
+>>>>>>> bd8abd5 (Better process pool..)
             executor.submit(bot_task, f"{username}@molodetz.nl", args.password)
         executor.shutdown(wait=True)