refactor: extract eval_expr helper and simplify eval_expressions loop

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.zshrc

@@ -40,6 +40,17 @@ source_file() {
   fi
 }
 
+# Eval the output of a command, silently skipping if it fails or produces nothing
+# Usage: eval_expr 'pyenv init -'
+eval_expr() {
+  local cmd="$1"
+  local output
+
+  if output="$(eval "$cmd" 2>/dev/null)" && [[ -n "$output" ]]; then
+    eval "$output"
+  fi
+}
+
 
 # =============================================================================
 # PATH EXTENSIONS
@@ -90,9 +101,7 @@ eval_expressions=(
 )
 
 for expr in "${eval_expressions[@]}"; do
-  if output="$(eval "$expr" 2>/dev/null)"; then
-    eval "$output"
-  fi
+  eval_expr "$expr"
 done