Fix DeepCompile profile metadata backfill (#8094)
DeepCompile ZeRO-3 scheduling can crash with KeyError or AssertionError
on missing device_time when graph profiling fails partway and leaves
some nodes without timing metadata.
This PR backfills default timing and memory metadata after profiling
cleanup so the profiler guarantees downstream passes see complete
metadata on every node.
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Signed-off-by: Masahiro Tanaka <mtanaka@anyscale.com>
