Add generic fx-graph serializer (NPTG) (#21032) #12475

Job	Run time
test-arm / test-backend-linux (arm_vgf_fp, operators) / linux-job	17m 56s
test-arm / test-backend-linux (arm_tosa_fp, operators) / linux-job	17m 0s
test-arm / test-backend-linux (arm_tosa_fp, models) / linux-job	17m 26s
test-arm / test-backend-linux (arm_vgf_fp, models) / linux-job	18m 54s
test-arm / test-backend-macos	-9s
test-arm / package-golden-artifacts	47s
	1h 11m 54s

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