Auto merge of #24752 - asajeffrey:split-surfman-chains-api-and-impl, r=jdm

Avoid recompiling script every time surfman changes

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Uses a version of webxr where webxr-api doesn't depend on surfman, so we can make changes to it without rebuilding script.

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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes do not require tests because it's just build issues

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0 files changed, 0 insertions, 0 deletions