Improve Katex error handling and fix handling of large expressions

* Make throwOnError=true the new default
* Handle JS errors as part of the RPC request/response flow
* Return a new Result type with .Err on it

This enables constructs on the form:

```handlebars
{{ with transform.ToMath "c = \\foo{a^2 + b^2}" }}
	{{ with .Err }}
	 	{{ warnf "error: %s" . }}
	{{ else }}
		{{ . }}
	{{ end }}
{{ end }}
```

Note that the new `Result` type behaves like `template.HTML` (or a string if needed) when printed, but it will panic if in a error state.

Closes #12748

1 files changed, 0 insertions, 0 deletions

diff --git a/internal/warpc/wasm/renderkatex.wasm b/internal/warpc/wasm/renderkatex.wasm
index c2b004d75..0afa10852 100644
--- a/internal/warpc/wasm/renderkatex.wasm
+++ b/internal/warpc/wasm/renderkatex.wasm