fix(shell): exponential backoff for persistent shell polling (#2996)

* fix(shell): replace fixed 10ms poll interval with exponential backoff to reduce WSL2 resource consumption

* fix(shell): rename _poll_interval to _poll_interval_start for clarity, update SSH override

* fix(shell): correctly rename _poll_interval to _poll_interval_start in ssh.py

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Co-authored-by: ygd58 <buraysandro9@gmail.com>

tools/environments/ssh.py

@@ -87,7 +87,7 @@ class SSHEnvironment(PersistentShellMixin, BaseEnvironment):
         except subprocess.TimeoutExpired:
             raise RuntimeError(f"SSH connection to {self.user}@{self.host} timed out")
 
-    _poll_interval: float = 0.15
+    _poll_interval_start: float = 0.15  # SSH: higher initial interval (150ms) for network latency
 
     @property
     def _temp_prefix(self) -> str: