Rework `GraphEdit` connections (drawing, API, optimizations) #20119

Job	Run time
📊 Static checks / Code style, file formatting, and docs	37s
🌐 Web / Template w/ threads (target=template_release, threads=yes)	1m 16s
🐧 Linux / Editor w/ Mono (target=editor)	7m 15s
🌐 Web / Template w/o threads (target=template_release, threads=no)	1m 10s
🐧 Linux / Editor with doubles and GCC sanitizers (target=editor, tests=yes, dev_build=yes, scu_build=yes, precision=double, use_asan=yes, use_ubsan=yes, linker=gold)	23m 21s
🐧 Linux / Editor with clang sanitizers (target=editor, tests=yes, dev_build=yes, use_asan=yes, use_ubsan=yes, use_llvm=yes, linker=lld)	11m 43s
🐧 Linux / Editor with ThreadSanitizer (target=editor, tests=yes, dev_build=yes, use_tsan=yes, use_llvm=yes, linker=lld)	11m 19s
🐧 Linux / Template w/ Mono (target=template_release)	1m 57s
🍎 macOS / Editor (target=editor, tests=yes)	15m 12s
🍎 macOS / Template (target=template_release)	7m 36s
🤖 Android / Template (target=template_release)	3m 56s
🐧 Linux / Minimal template (target=template_release, everything disabled)	1m 24s
🍏 iOS / Template (target=template_release)	3m 0s
🏁 Windows / Editor (target=editor, tests=yes)	14m 45s
🏁 Windows / Template (target=template_release)	7m 28s
🪲 Godot CPP / Build and test Godot CPP	7m 5s
	1h 59m 4s

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