feat(seed): SeedResult outcome, capped preview, advisory, count cap (ADR-0048 P1.3c)

A dedicated SeedResult replaces the borrowed insert outcome (X5):
- CommandOutcome::Seed + DslSeedSucceeded event + handle_dsl_seed_success
  render: the echo, "N row(s) seeded into T", a capped preview table
  (D18, first 20 rows; full count always reported), and a Hint-styled
  advisory naming enum-ish / un-derivable-CHECK columns filled with
  generic text (D12/D13, Phase-1 wording).
- SeedResult carries requested vs produced, so a junction cap is now
  reported to the user, not only logged.
- Count cap (D6): a seed over 10000 rows is refused with a friendly error.
- Catalog keys ok.rows_seeded / seed.capped / seed.advisory_generic.

4 new tests (advisory flag, IN-check not flagged, preview cap, excess
count). 2346 pass / 0 fail / 0 skip, clippy clean.

src/app.rs

@@ -771,6 +771,10 @@ impl App {
                 self.handle_dsl_insert_success(&command, &result);
                 Vec::new()
             }
+            AppEvent::DslSeedSucceeded { command, result } => {
+                self.handle_dsl_seed_success(&command, &result);
+                Vec::new()
+            }
             AppEvent::DslUpdateSucceeded {
                 command,
                 result,
@@ -2072,6 +2076,34 @@ impl App {
         }
     }
 
+    /// Render a successful `seed` (ADR-0048): the ✓ echo, the seeded-row
+    /// count (with a cap note when the unique-value space ran out), the
+    /// capped preview table (D18), and a Hint-styled advisory naming
+    /// columns filled with generic text that look like fixed value sets
+    /// (D12/D13).
+    fn handle_dsl_seed_success(&mut self, command: &Command, result: &crate::db::SeedResult) {
+        self.note_ok_summary(command);
+        let mut summary = crate::t!(
+            "ok.rows_seeded",
+            count = result.produced,
+            table = result.table
+        );
+        if result.produced < result.requested {
+            summary.push(' ');
+            summary.push_str(&crate::t!("seed.capped", requested = result.requested));
+        }
+        self.note_system(summary);
+        for line in crate::output_render::render_data_table(&result.data) {
+            self.note_system(line);
+        }
+        if !result.advisory_columns.is_empty() {
+            self.push_category_three_prose(crate::t!(
+                "seed.advisory_generic",
+                columns = result.advisory_columns.join(", ")
+            ));
+        }
+    }
+
     fn handle_dsl_update_success(&mut self, command: &Command, result: &UpdateResult) {
         self.note_ok_summary(command);
         self.note_system(crate::t!("ok.rows_updated", count = result.rows_affected));