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/timeline/seed.rs

@@ -5,7 +5,7 @@ use tracing::debug;
 
 use super::types::{
     EntityRef, MatchedDiscussion, TimelineEvent, TimelineEventType, resolve_entity_by_iid,
-    resolve_entity_ref, truncate_to_chars,
+    resolve_entity_ref,
 };
 use crate::core::error::Result;
 use crate::embedding::ollama::OllamaClient;
@@ -337,7 +337,7 @@ fn find_evidence_notes(
             proj_id,
         ) = row_result?;
 
-        let snippet = truncate_to_chars(body.as_deref().unwrap_or(""), 200);
+        let snippet = body.as_deref().unwrap_or("").to_owned();
 
         let entity_ref = resolve_entity_ref(conn, &parent_type, parent_entity_id, Some(proj_id))?;
         let (iid, project_path) = match entity_ref {