Fix some CRAN policy issues

Change-Id: I6862ea1bfbadbaf5d6090b6655c21ecf66650c16
diff --git a/demo/corpus_size_by_year.R b/demo/corpus_size_by_year.R
index 853b629..5010d08 100644
--- a/demo/corpus_size_by_year.R
+++ b/demo/corpus_size_by_year.R
@@ -4,7 +4,6 @@
 #
 library(RKorAPClient)
 library(ggplot2)
-library(scales)  # For comma_format()
 
 # Define years to analyze
 years <- 1990:2024
@@ -26,7 +25,7 @@
 g <- ggplot(corpus_data, aes(x = year, y = tokens)) +
   geom_col(fill = "steelblue", alpha = 0.7) +
   scale_x_continuous(breaks = seq(1990, 2024, 5)) +
-  scale_y_continuous(labels = scales::comma_format()) +
+  scale_y_continuous(labels = function(x) format(x, big.mark = ",", scientific = FALSE)) +
   labs(
     title = "Corpus Size by Year - Stern Magazine",
     subtitle = "Number of tokens in DeReKo",
diff --git a/demo/regional.R b/demo/regional.R
index cf31ab7..10b5f82 100755
--- a/demo/regional.R
+++ b/demo/regional.R
@@ -1,7 +1,7 @@
 #!/usr/bin/Rscript
 library(RKorAPClient)
 library(ggplot2)
-library(sf)
+## sf is used via sf::; don't attach package in demo to avoid undeclared library() calls
 # library(R.cache)
 
 devAskNewPage(ask = FALSE)