zsh: Move PATH changes to .zprofile

zsh/.zprofile

@@ -0,0 +1,27 @@
+source_if() {
+    if [ -e "$1" ]; then
+        source "$1"
+    fi
+}
+
+path_if() {
+    if [ -d "$1" ]; then
+        case ":$PATH:" in
+            *:"$1":*)
+                ;;
+            *)
+                PATH="${1}${PATH:+:$PATH}"
+        esac
+    fi
+}
+
+source_if "${HOME}/.nix-profile/etc/profile.d/nix.sh"
+
+path_if "$HOME/bin"
+path_if "$HOME/.local/bin"
+path_if /usr/local/bin
+path_if /opt/homebrew/bin
+path_if /opt/homebrew/sbin
+
+unset -f source_if
+unset -f path_if