Set `$schema` as first attribute

[peterdesmet]

$schema should be the first property of package, resource, schema. That makes the JSON file easier to read.

• When creating an object from scratch, that is easy. Just define it first. create_package(), create_schema and add_resource() already do this.
• When manipulating an object that already has properties, it's harder (i.e. what the upgrade_ functions do). You need to use append() or alike.

The issue is that append() drops any custom attributes and class, which are required for functions that use that object.

library(frictionless)
p <- example_package()
attributes(p)
#> $names
#> [1] "name"      "id"        "licenses"  "version"   "created"   "spatial"  
#> [7] "temporal"  "resources"
#> 
#> $directory
#> [1] "/Library/Frameworks/R.framework/Versions/4.5-arm64/Resources/library/frictionless/extdata/v1"
#> 
#> $class
#> [1] "datapackage" "list"

p <- append(p, list("$schema" = "just added"), after = 0)
attributes(p)
#> $names
#> [1] "$schema"   "name"      "id"        "licenses"  "version"   "created"  
#> [7] "spatial"   "temporal"  "resources"

^{Created on 2026-08-26 with reprex v2.1.1}

TODO

• Is there a way to solve this in purrr()? Note that prepend() (deprecated) has the same issue.
• Is there a way to solve this without a helper function?
• Should frictionless have its own append() function? See discussion at append() drops custom datapackage class #198
• Once implemented, revert 036bb52

[PietrH]

@peterdesmet Is the order of the other attributes also important?