refactor(cli): adopt flex-width rendering, remove data-layer truncation

Replace hardcoded truncation widths across CLI commands with
render::flex_width() calls that adapt to terminal size. Remove
server-side truncate_to_chars() in timeline collect/seed stages so
full text is preserved through the pipeline — truncation now happens
only at the presentation layer where terminal width is known.

Affected commands: explain, file-history, list (issues/mrs/notes),
me, timeline, who (active/expert/workload).

src/cli/commands/list/issues.rs

@@ -359,10 +359,10 @@ pub fn print_list_issues(result: &ListResult) {
     }
     headers.extend(["Assignee", "Labels", "Disc", "Updated"]);
 
-    let mut table = LoreTable::new().headers(&headers).align(0, Align::Right);
+    let mut table = LoreTable::new().headers(&headers).align(0, Align::Right).flex_col(1);
 
     for issue in &result.issues {
-        let title = render::truncate(&issue.title, 45);
+        let title = issue.title.clone();
         let relative_time = render::format_relative_time_compact(issue.updated_at);
         let labels = render::format_labels_bare(&issue.labels, 2);
         let assignee = format_assignees(&issue.assignees);