This allows fusing nested `.padding` modifiers into a single `div` that sums up padding values from all these modifiers.
Before:
```swift
Text("text").padding(10).padding(20)
```
rendered to this (text styling omitted for brevity):
```html
<div style="padding-top: 20.0px; padding-left: 20.0px; padding-bottom: 20.0px; padding-right: 20.0px;">
<div style="padding-top: 10.0px; padding-left: 10.0px; padding-bottom: 10.0px; padding-right: 10.0px;">
<span>text</span>
</div>
</div>
```
Now it renders as
```html
<div style="padding-top: 30.0px; padding-left: 30.0px; padding-bottom: 30.0px; padding-right: 30.0px;">
<span>text</span>
</div>
```
I hope this approach could be applied to other modifier combinations where it makes sense (in separate PRs).
* Attempt `padding` modifier fusion
* Fix linter warning
* Add a test to verify that fusion works
* Enable fusion of modifiers nested three times
* Filter out empty attributes
* Run snapshot tests only on macOS for now
* Fully exclude snapshot testing on WASI
* Fix `testOptional` snapshot
* Clean up code formatting
Our OpenCombine fork no longer depends on Runtime, and we don't need much from it other than struct metadata. I removed the unused bits and bobs and kept only a minimal subset of it that we really need. This should make it easier for us to test and debug, as #367 has shown that some weird stuff may still lurk in that area.
* Add a test for environment injection
We had some issues in this code area previously and I'm thinking of refactoring it in attempt to fix#367. Would be great to increase the test coverage here before further refactoring.
* Update copyright years in `MountedElement.swift`
* Update copyright years in the rest of the files
* Vend the Runtime library directly
* Remove unused class, enum, tuple, func reflection
* Remove unused models and protocol metadata
* Remove unused MetadataType and NominalMetadataType
* Remove unused protocols, rename RelativePointer
* Remove more unused protocols
* Use immutable pointers for reflection
* Update copyright headers
Yuta Saito