mdman: use cargo build-man everywhere

ci/validate-man.sh

@@ -3,24 +3,25 @@
 
 set -e
 
-cd src/doc
+cargo_man="src/doc"
+mdman_man="crates/mdman/doc"
 
-changes=$(git status --porcelain -- .)
+changes=$(git status --porcelain -- $cargo_man $mdman_man)
 if [ -n "$changes" ]
 then
     echo "git directory must be clean before running this script."
     exit 1
 fi
 
-./build-man.sh
+cargo build-man
 
-changes=$(git status --porcelain -- .)
+changes=$(git status --porcelain -- $cargo_man $mdman_man)
 if [ -n "$changes" ]
 then
-    echo "Detected changes of man pages in src/doc:"
+    echo "Detected changes of man pages:"
     echo "$changes"
     echo
-    echo "Please run './build-man.sh' in the src/doc directory to rebuild the"
-    echo "man pages, and commit the changes."
+    echo 'Please run `cargo build-man` to rebuild the man pages'
+    echo "and commit the changes."
     exit 1
 fi

src/doc/README.md

@@ -50,11 +50,7 @@ directory) to three different formats:
 3. Plain text (needed for embedded man pages on platforms without man such as
    Windows), saved in [`src/doc/man/generated_txt/`](man/generated_txt).
 
-To rebuild the man pages, run the script `build-man.sh` in the `src/doc` directory.
-
-```console
-$ ./build-man.sh
-```
+To rebuild the man pages, run `cargo build-man` inside the workspace.
 
 ### SemVer chapter tests