fix: handle disabled text outputs properly

Co-authored-by: aider (openai/andrew/openrouter/deepseek/deepseek-chat-v3.1) <aider@aider.chat>

src/meta_plugin/text.rs

@@ -48,6 +48,29 @@ impl TextMetaPlugin {
             outputs,
         );
         
+        // Set disabled outputs to null based on options
+        let outputs_to_disable = vec![
+            ("text_word_count", "text_word_count"),
+            ("text_line_count", "text_line_count"),
+            ("text_line_max_len", "text_line_max_len"),
+            ("text_line_mean_len", "text_line_mean_len"),
+            ("text_line_median_len", "text_line_median_len"),
+        ];
+        
+        for (option_name, output_name) in outputs_to_disable {
+            if let Some(value) = base.options.get(option_name) {
+                // Handle both boolean false and string "false"
+                let should_disable = match value {
+                    serde_yaml::Value::Bool(b) => !b,
+                    serde_yaml::Value::String(s) => s == "false",
+                    _ => false,
+                };
+                if should_disable {
+                    base.outputs.insert(output_name.to_string(), serde_yaml::Value::Null);
+                }
+            }
+        }
+        
         // Set default options if not provided
         let default_options = vec![
             ("text_detect_size", serde_yaml::Value::Number(PIPESIZE.into())),