docs: Use a better input example in the streaming section (#3322)

The introduction says all the usage examples (e.g. of truncate_stream,
etc) in the section use [0,[1]] as input, but they actually use [1,[2]].
["a",["b"]] seems better than [1,[2]] as the string values won't be
confusable with the indexes in <path>.

jq.1.prebuilt

@@ -1,5 +1,5 @@
 .
-.TH "JQ" "1" "January 2025" "" ""
+.TH "JQ" "1" "May 2025" "" ""
 .
 .SH "NAME"
 \fBjq\fR \- Command\-line JSON processor
@@ -3791,7 +3791,7 @@ However, streaming isn\'t easy to deal with as the jq program will have \fB[<pat
 Several builtins are provided to make handling streams easier\.
 .
 .P
-The examples below use the streamed form of \fB[0,[1]]\fR, which is \fB[[0],0],[[1,0],1],[[1,0]],[[1]]\fR\.
+The examples below use the streamed form of \fB["a",["b"]]\fR, which is \fB[[0],"a"],[[1,0],"b"],[[1,0]],[[1]]\fR\.
 .
 .P
 Streaming forms include \fB[<path>, <leaf\-value>]\fR (to indicate any scalar value, empty array, or empty object), and \fB[<path>]\fR (to indicate the end of an array or object)\. Future versions of jq run with \fB\-\-stream\fR and \fB\-\-seq\fR may output additional forms such as \fB["error message"]\fR when an input text fails to parse\.
@@ -3803,9 +3803,9 @@ Consumes a number as input and truncates the corresponding number of path elemen
 .
 .nf
 
-jq \'truncate_stream([[0],1],[[1,0],2],[[1,0]],[[1]])\'
+jq \'truncate_stream([[0],"a"],[[1,0],"b"],[[1,0]],[[1]])\'
    1
-=> [[0],2], [[0]]
+=> [[0],"b"], [[0]]
 .
 .fi
 .
@@ -3818,9 +3818,9 @@ Outputs values corresponding to the stream expression\'s outputs\.
 .
 .nf
 
-jq \'fromstream(1|truncate_stream([[0],1],[[1,0],2],[[1,0]],[[1]]))\'
+jq \'fromstream(1|truncate_stream([[0],"a"],[[1,0],"b"],[[1,0]],[[1]]))\'
    null
-=> [2]
+=> ["b"]
 .
 .fi
 .