"File is Locked" message for a folder with thousands of subfolders/files
I found a perfect terminal set of commands buried in a forum post here: https://forums.macrumors.com/threads/how-to-batch-unlock-numerous-files-within-subfolders-folders-directory.453818/

Here's the commands I used (my project was located at /APPS/MYAPP):

export UNLOCK=/APPS/MYAPP
find $UNLOCK -type f -exec setfile -a l {} \;
find $UNLOCK -type d -exec setfile -a l {} \;


The type argument is f for files, d for directories. 

The exec argument passes setfile, from the xcode developer tools (may need to be installed first), and uses lower-case L to "unlock" (bizarre command line syntax, I know)