Fix project-install.sh and default profile structure

Two issues fixed:

1. Default profile had wrong structure - categories were directly in
   profile root instead of inside `standards/` subfolder.
   Moved `global/` into `standards/global/`.

2. Script crashed with `set -e` due to arithmetic expression returning
   exit code 1 when chain_depth was 0. Changed post-increment to
   pre-increment so the expression always returns non-zero.

Author: Perlover

profiles/default/global/tech-stack.md …s/default/standards/global/tech-stack.mdprofiles/default/global/tech-stack.md renamed to profiles/default/standards/global/tech-stack.md profiles/default/global/tech-stack.md renamed to profiles/default/standards/global/tech-stack.md

@@ -447,7 +447,7 @@ main() {
             done
             chain_display="$chain_display"$'\n'"$indent  ↳ inherits from: $profile_name"
         fi
-        ((chain_depth++))
+        ((++chain_depth))
     done <<< "$reversed_chain"
     echo "$chain_display"