Feat: Graceful Handling of First-touch API Call (App List)

[DeepanshKhurana]

Have you read the Contributing Guidelines? ✅

Closes #11
Related to #10

Description

• Handle the case where the API works but has no apps (reactableLang's noData for the app table)
• Handle the case where the API itself fails by adding a new, more relevant empty state
• Minor fixes for CSS and strings
• Update README.md with FAQs

The GIF below illustrates the changes/cases.

Definition of Done

• The change is thoroughly documented.
• The CI passes (R CMD check, linter, unit tests, spelling).
• Any generated files have been updated (e.g. .Rd files with roxygen2::roxygenise())

[Gotfrid]

Nice work, thank you for your rapid reaction to an opened issue 💯
Approved with a few non-critical comments.

Another comment (out of scope of this PR) I have is related to a pattern that I see in main.R and which I find weird:

observeEvent(..., { renderUI(mod$ui()); mod$server() }

Would it be cleaner if you create ui+server for a particular app section only once, and inside a corresponding server you decide what to render by passing a reactive key, e.g. state$selected_app()$guid?

[Gotfrid]

nitpick: prefer trailing comma

[Gotfrid]

suggestion: i think it's better to make a function that is not shiny-specific, i.e. remove renderUI from it. This way you can control what to do with the output of this function - use it in the server, or in the ui function.

[Gotfrid]

nitpick: ignoreInit = FALSE is the default value, no need to specify it.

[Gotfrid]

suggestion: prefer `inherits(app_list(), "data.frame")
example:

x <- dplyr::as_tibble(mtcars)
class(x) # "tbl_df"     "tbl"        "data.frame"
class(x) != "data.frame" TRUE  TRUE FALSE
inherits(x, "data.frame") # TRUE

[DeepanshKhurana]

Thank you @Gotfrid for all the suggestions. I've made changes and merged them. For the comment about the reactivity flow, I can't think of the original reason for taking that route in implementation. I agree with you that it is a bit awkward and can be refactored. Documented this as an enhancement issue (#13)