invalidate_loaded_state

FdtdSession.invalidate_loaded_state() → None

Mark the in-memory FDTD state as no longer matching any file.

Call this after any operation that mutates the in-memory scene (switchtolayout, set, geometry edits, mode changes) so a later load_if_needed() of the previously cached file actually re-reads the on-disk version.

Also clears the getresult cache: a mutation to the in-memory state may invalidate previously fetched monitor data (e.g. switching to layout mode discards results), so we pessimistically drop every cached entry rather than guessing which keys survived the mutation.