fix: harden JetBrains remote config sync to prevent IDE freezes (#11891)

Remove Sentry error reporting from the sync catch block — the
service<ContinueSentryService>() call could itself throw from the
background thread, letting the original exception escape and silently
killing all future scheduled runs of the sync task.

Replace with IDEA Logger warnings so failures are visible in the IDE
log. Add explicit connect/read timeouts (5s) to prevent a hung server
from blocking the shared executor indefinitely. Early-return when the
remote config URL is not configured so no work is done at all.

Remove redundant addRemoteSyncJob() call from settings reset(), which
only restores UI fields and should not restart the sync.

Ref: https://github.com/continuedev/continue/discussions/8606#discussioncomment-15003299