complete category-scoped values, rules, and report parity

- Add category-bound date and numeric values
- Complete rule execution and conflict handling
- Expand Markdown and HTML report output

src/model/settings.rs

@@ -14,6 +14,7 @@ pub struct DocumentSettings {
     pub afternoon_time: String,
     pub evening_time: String,
     pub note_tab_width: u8,
+    pub report_headers: bool,
 }
 
 impl Default for DocumentSettings {
@@ -31,6 +32,7 @@ impl Default for DocumentSettings {
             afternoon_time: "13:00".into(),
             evening_time: "18:00".into(),
             note_tab_width: 4,
+            report_headers: true,
         }
     }
 }