_flash_line validates image_size and returns the formatted line, so
nothing after a print can raise and the line buffer, the image_size
double-lookup, and the blanket's one known trigger all dissolve; the
blanket keeps its charter (a test now drives it with a patched raise).
_find_app_partition_size returns None for legitimate absence and
reserves raises for a present-but-broken table, dissolving the
_MalformedPartitionRow subclass and the except-ordering it relied on;
run_compile passes the table path unconditionally so the module owns
the whole policy. The is_file pre-check folds into the OSError arm,
the dead or-{} is gone, and the tests share _dram_size_data and
_write_partitions instead of repeating payload literals.