refactor: use shared.ToLittleEndian in NV graphics commands

[adcondev]

Replaced manual endian conversion with shared.ToLittleEndian in DefineNVRasterGraphics and DefineNVColumnGraphics to improve maintainability and readability.
Verified with existing tests.

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PR created automatically by Jules for task 12340671953173908283 started by @adcondev

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[github-actions]

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[github-actions]

⚡ Benchmark Results

📈 Performance Comparison

📊 Click to expand detailed results

Current Branch Results

BenchmarkNewDocument-4    	1000000000	         0.3118 ns/op	       0 B/op	       0 allocs/op
BenchmarkBuildSimple-4    	 3717924	       331.5 ns/op	     240 B/op	       4 allocs/op
BenchmarkBuildComplex-4   	  432972	      2697 ns/op	    1809 B/op	      25 allocs/op
BenchmarkToJSON-4         	  554349	      2061 ns/op	     592 B/op	       3 allocs/op
BenchmarkParseDocument_Minimal-4    	  513084	      2348 ns/op	     568 B/op	      14 allocs/op
BenchmarkParseDocument_Receipt-4    	   94794	     12531 ns/op	    2392 B/op	      34 allocs/op
BenchmarkCommandUnmarshal_Text-4    	  417067	      2668 ns/op	     568 B/op	      19 allocs/op
BenchmarkCommandUnmarshal_Table-4   	  275379	      4152 ns/op	     944 B/op	      21 allocs/op
BenchmarkTextCommandParsing-4       	  523556	      2120 ns/op	     544 B/op	      16 allocs/op
BenchmarkTableCommandParsing-4      	  242851	      4766 ns/op	    1000 B/op	      29 allocs/op
BenchmarkParseHexString-4           	 8014220	       138.3 ns/op	      48 B/op	       2 allocs/op
BenchmarkCleanHexString-4           	 6685690	       178.4 ns/op	      64 B/op	       2 allocs/op
BenchmarkContainsSequence-4         	364130007	         3.282 ns/op	       0 B/op	       0 allocs/op
BenchmarkCheckCriticalCommands-4    	31814955	        33.22 ns/op	       0 B/op	       0 allocs/op
BenchmarkDocument_Validate-4       	14560065	        82.56 ns/op	       0 B/op	       0 allocs/op
BenchmarkParseDocument_Simple-4    	  498002	      2392 ns/op	     568 B/op	      14 allocs/op
BenchmarkParseDocument_Complex-4   	  139563	      8466 ns/op	    1352 B/op	      26 allocs/op
BenchmarkPrintImage_Small-4             	     597	   2012668 ns/op	 3469945 B/op	      24 allocs/op
BenchmarkPrintImage_Medium-4            	     322	   3632303 ns/op	 5481088 B/op	      24 allocs/op
BenchmarkPrintImage_ThermalPreview-4    	     142	   8500678 ns/op	 5235269 B/op	  230723 allocs/op

Base Branch Results

BenchmarkNewDocument-4    	1000000000	         0.3174 ns/op	       0 B/op	       0 allocs/op
BenchmarkBuildSimple-4    	 3693643	       333.9 ns/op	     240 B/op	       4 allocs/op
BenchmarkBuildComplex-4   	  387930	      2722 ns/op	    1809 B/op	      25 allocs/op
BenchmarkToJSON-4         	  541557	      2076 ns/op	     592 B/op	       3 allocs/op
BenchmarkParseDocument_Minimal-4    	  507884	      2323 ns/op	     568 B/op	      14 allocs/op
BenchmarkParseDocument_Receipt-4    	   93751	     12542 ns/op	    2392 B/op	      34 allocs/op
BenchmarkCommandUnmarshal_Text-4    	  419800	      2691 ns/op	     568 B/op	      19 allocs/op
BenchmarkCommandUnmarshal_Table-4   	  274760	      4146 ns/op	     944 B/op	      21 allocs/op
BenchmarkTextCommandParsing-4       	  533992	      2156 ns/op	     544 B/op	      16 allocs/op
BenchmarkTableCommandParsing-4      	  244514	      4780 ns/op	    1000 B/op	      29 allocs/op
BenchmarkParseHexString-4           	 8761282	       135.0 ns/op	      48 B/op	       2 allocs/op
BenchmarkCleanHexString-4           	 6707832	       177.8 ns/op	      64 B/op	       2 allocs/op
BenchmarkContainsSequence-4         	367328049	         3.274 ns/op	       0 B/op	       0 allocs/op
BenchmarkCheckCriticalCommands-4    	36298153	        38.04 ns/op	       0 B/op	       0 allocs/op
BenchmarkDocument_Validate-4       	14505909	        82.98 ns/op	       0 B/op	       0 allocs/op
BenchmarkParseDocument_Simple-4    	  499987	      2394 ns/op	     568 B/op	      14 allocs/op
BenchmarkParseDocument_Complex-4   	  138100	      8587 ns/op	    1352 B/op	      26 allocs/op
BenchmarkPrintImage_Small-4             	     606	   1937514 ns/op	 3469935 B/op	      24 allocs/op
BenchmarkPrintImage_Medium-4            	     325	   3728307 ns/op	 5481085 B/op	      24 allocs/op
BenchmarkPrintImage_ThermalPreview-4    	     136	   8843331 ns/op	 5235274 B/op	  230723 allocs/op

💡 Note: Use benchstat for statistical comparison

🎯 Summary

• Total Benchmarks: 32
• Average Speed: 2578951 ns/op
• Average Memory: 2396936 B/op
• Average Allocations: 41093 allocs/op