chore(r): add spelling check via usethis::use_spell_check()

pkg-r/DESCRIPTION

@@ -41,13 +41,16 @@ Suggests:
     later,
     rmarkdown,
     shinytest2,
+    spelling,
     testthat (>= 3.0.0),
     withr
 VignetteBuilder: 
     knitr,
     rmarkdown
+Config/needs/check: spelling
 Config/Needs/website: pkgdown, tidyverse/tidytemplate
 Config/roxygen2/version: 8.1.0
 Config/testthat/edition: 3
 Encoding: UTF-8
+Language: en-US
 Roxygen: list(markdown = TRUE)

pkg-r/R/input-handler.R

@@ -11,7 +11,7 @@
 #' The contract, stated in terms of the JSON the React hook sent:
 #'
 #' * **Array of objects** (`[{a: 1}, {b: 2}]`) — kept as a list of records
-#'   This is the case shiny's default handler gets wrong.
+#'   This is the case Shiny's default handler gets wrong.
 #' * **Array of scalars** (`[0, 100]`, `["a", "b"]`) — flattened to an atomic
 #'   vector, exactly as shiny does by default.
 #' * **Empty array** (`[]`) — `list()`, matching Python's `[]`. Shiny's default

pkg-r/inst/WORDLIST

@@ -0,0 +1,50 @@
+Buie
+DOM
+HMR
+JS
+JSX
+Lifecycle
+Matchers
+ORCID
+PBC
+ROR
+ReactDOM
+Shiny's
+TSX
+TypeScript
+UI
+Vite
+Vue's
+btw
+bundler
+bundler's
+codebase
+debounce
+dep
+deserializer
+dev
+funder
+jQuery
+js
+jsonlite
+lifecycle
+matcher
+mtime
+namespaced
+npm
+passthrough
+renderer's
+renderers
+runnable
+serializable
+shinyreact's
+shinytest
+stylesheet
+templating
+theming
+truthy
+tsx
+ui
+untyped
+websocket
+zzz

pkg-r/tests/spelling.R

@@ -0,0 +1,7 @@
+if (requireNamespace('spelling', quietly = TRUE)) {
+  spelling::spell_check_test(
+    vignettes = TRUE,
+    error = FALSE,
+    skip_on_cran = TRUE
+  )
+}