code blocks for news file

Author: jangorecki

NEWS.md

@@ -224,38 +224,38 @@
     ```
 
 18. New `frolladapt` helper function has been added to aid in preparation of adaptive length of rolling window width when dealing with _irregularly spaced ordered data_. This lets the user to apply a rolling function over a period without having to deal with gaps in a data where some periods might be missing, [#3241](https://github.com/Rdatatable/data.table/issues/3241). Thanks to @jangorecki for implementation.
-```r
-idx = as.Date("2025-09-08") + c(0,1,4,5,6,7,9,10,14)
-dt = data.table(index=idx, value=seq_along(idx))
-dt
-#        index value
-#       <Date> <int>
-#1: 2025-09-08     1
-#2: 2025-09-09     2
-#3: 2025-09-12     3
-#4: 2025-09-13     4
-#5: 2025-09-14     5
-#6: 2025-09-15     6
-#7: 2025-09-17     7
-#8: 2025-09-18     8
-#9: 2025-09-22     9
-dt[, c("rollmean3","rollmean3days") := list(
-  frollmean(value, 3),
-  frollmean(value, frolladapt(index, 3), adaptive=TRUE)
-  )]
-dt
-#        index value rollmean3 rollmean3days
-#       <Date> <int>     <num>         <num>
-#1: 2025-09-08     1        NA            NA
-#2: 2025-09-09     2        NA            NA
-#3: 2025-09-12     3         2           3.0
-#4: 2025-09-13     4         3           3.5
-#5: 2025-09-14     5         4           4.0
-#6: 2025-09-15     6         5           5.0
-#7: 2025-09-17     7         6           6.5
-#8: 2025-09-18     8         7           7.5
-#9: 2025-09-22     9         8           9.0
-```
+    ```r
+    idx = as.Date("2025-09-08") + c(0,1,4,5,6,7,9,10,14)
+    dt = data.table(index=idx, value=seq_along(idx))
+    dt
+    #        index value
+    #       <Date> <int>
+    #1: 2025-09-08     1
+    #2: 2025-09-09     2
+    #3: 2025-09-12     3
+    #4: 2025-09-13     4
+    #5: 2025-09-14     5
+    #6: 2025-09-15     6
+    #7: 2025-09-17     7
+    #8: 2025-09-18     8
+    #9: 2025-09-22     9
+    dt[, c("rollmean3","rollmean3days") := list(
+      frollmean(value, 3),
+      frollmean(value, frolladapt(index, 3), adaptive=TRUE)
+      )]
+    dt
+    #        index value rollmean3 rollmean3days
+    #       <Date> <int>     <num>         <num>
+    #1: 2025-09-08     1        NA            NA
+    #2: 2025-09-09     2        NA            NA
+    #3: 2025-09-12     3         2           3.0
+    #4: 2025-09-13     4         3           3.5
+    #5: 2025-09-14     5         4           4.0
+    #6: 2025-09-15     6         5           5.0
+    #7: 2025-09-17     7         6           6.5
+    #8: 2025-09-18     8         7           7.5
+    #9: 2025-09-22     9         8           9.0
+    ```
 
 ### BUG FIXES