ai: apply changes for #876 (1 review thread)

Addresses:
  - #3636374430 at src/databricks/sql/auth/oauth.py:215

Signed-off-by: peco-engineer-bot[bot] <peco-engineer-bot[bot]@users.noreply.github.com>

Author: peco-engineer-bot[bot]

src/databricks/sql/auth/oauth.py

@@ -205,13 +205,22 @@ def _on_timeout():
                 self.redirect_port = port
                 break
             except OSError as e:
+                # Record every bind-time OSError so the fall-through
+                # `raise last_error` below always re-raises a real exception.
+                # If we only recorded the port-in-use case, an unexpected error
+                # on every port (e.g. EACCES, EADDRNOTAVAIL) would leave
+                # last_error == None and turn `raise last_error` into
+                # `raise None`, masking the real failure with a confusing
+                # TypeError.
+                last_error = e
                 # errno.EADDRINUSE resolves to the platform's value (48 on
                 # macOS, 98 on Linux), so a port-in-use bind failure is
-                # recognized cross-platform. Otherwise last_error stays None on
-                # Linux and `raise last_error` below becomes `raise None`.
+                # recognized cross-platform and downgraded to an info log while
+                # we try the next port.
                 if e.errno == errno.EADDRINUSE:
                     logger.info(f"Port {port} is in use")
-                    last_error = e
+                else:
+                    logger.warning(f"Unexpected error binding port {port}: {e}")
             except webbrowser.Error as e:
                 # No browser could be launched at all (webbrowser.get() found no
                 # runnable browser). This is a strong, reliable headless signal