fix: cover tui in the CLI inventory and drop the em-dashes it printed

The inventory test predates the `tui` command, so a rename or an
accidental removal would have gone unnoticed: it now asserts the command,
its `-l`/`--list` flag and its optional position operand.

The digest and search-result lines joined their halves with an em-dash,
which the repo's own convention rules out, so both now use the middle dot
the surrounding lines already use. The one em-dash left in `src/tui/` is
load-bearing: `search-service.ts` builds a session snippet with it, and
the pattern that strips the repeated label has to match it.

Also moves `buildSearchEntries`'s doc comment back onto
`buildSearchEntries`; it had ended up stacked above a helper.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/tui/tui-app.ts

@@ -1399,7 +1399,7 @@ class TuiApp {
     }
     // Nothing to switch to (a history or file hit), so the row's own facts are
     // the answer; resuming one is phase 3.
-    this.model.updateSearch({ note: [entry.text, entry.detail].filter((part) => part).join(' — ') });
+    this.model.updateSearch({ note: [entry.text, entry.detail].filter((part) => part).join(' · ') });
   }
 
   private async openDigest(): Promise<void> {