Clarify -f argument parsing

Author: thaliaarchi

docs/content/manual/dev/manual.yml

@@ -221,10 +221,11 @@ sections:
         RS.  This mode also parses the output of jq without the `--seq`
         option.
 
-      * `-f filename` / `--from-file filename`:
+      * `-f` / `--from-file`:
 
-        Read filter from the file rather than from a command line, like
-        awk's -f option.
+        Read filter from a file rather than from a command line, like
+        awk's -f option. This changes the filter argument to be
+        interpreted as a filename, instead of the source of a program.
 
       * `-L directory` / `--library-path directory`:
 

jq.1.prebuilt

@@ -94,7 +94,7 @@ static void usage(int code, int keep_it_short) {
       "      --stream-errors       implies --stream and report parse error as\n"
       "                            an array;\n"
       "      --seq                 parse input/output as application/json-seq;\n"
-      "  -f, --from-file file      load filter from the file;\n"
+      "  -f, --from-file           load filter from a file;\n"
       "  -L, --library-path dir    search modules from the directory;\n"
       "      --arg name value      set $name to the string value;\n"
       "      --argjson name value  set $name to the JSON value;\n"