feat: Add support for tabular/csv data input.

crates/pikl-core/src/model/event.rs

@@ -81,12 +81,24 @@ pub struct ViewState {
     pub mode: Mode,
     pub selection_count: usize,
     pub multi_enabled: bool,
+    /// Column headers for table mode. None when not in
+    /// table mode.
+    pub columns: Option<Vec<ColumnHeader>>,
     /// Monotonically increasing counter. Each call to
     /// `build_view_state()` bumps this, so frontends can
     /// detect duplicate broadcasts and skip redundant redraws.
     pub generation: u64,
 }
 
+/// Column header with display name and computed width for
+/// table mode rendering.
+#[must_use]
+#[derive(Debug, Clone)]
+pub struct ColumnHeader {
+    pub display_name: String,
+    pub width: u16,
+}
+
 /// A single item in the current viewport window. Has the
 /// display label pre-resolved and the position in the
 /// filtered list.
@@ -97,6 +109,9 @@ pub struct VisibleItem {
     pub formatted_text: Option<String>,
     pub index: usize,
     pub selected: bool,
+    /// Column cell values for table mode. None when not in
+    /// table mode.
+    pub column_values: Option<Vec<String>>,
 }
 
 /// Final outcome of [`crate::menu::MenuRunner::run`]. The