avm2: Add CustomConstructor metadata to define custom native constructors #26449

Job	Run time
Paths filter	7s
Build for browser tests	1m 53s
Test Node.js 20 / ubuntu-24.04	4m 2s
Test Node.js ${{ matrix.node_version }} / ${{ matrix.os }}	0s
Test Node.js 20 / windows-latest	7m 35s
Test Node.js 22 / ubuntu-24.04	3m 59s
Test Node.js 22 / windows-latest	7m 27s
Test in ${{ matrix.browser }}	0s
Test in chrome	1m 51s
Test in firefox	2m 52s
Test in edge	2m 8s
	31m 54s

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