Add --id flag to bd list for filtering by specific issue IDs

- Add --id flag accepting comma-separated IDs
- Implements ID filtering at CLI, RPC, and storage layers
- Normalizes IDs (trim, dedupe, remove empty) like labels
- Guards against excessive ID lists (max 1000)
- Works with other filters (status, priority, etc.)

Closes bd-200

Amp-Thread-ID: https://ampcode.com/threads/T-377464f2-1e7f-46f9-b23e-1e3cfd611061
Co-authored-by: Amp <amp@ampcode.com>

internal/storage/sqlite/sqlite.go

@@ -1705,6 +1705,16 @@ func (s *SQLiteStorage) SearchIssues(ctx context.Context, query string, filter t
 		whereClauses = append(whereClauses, fmt.Sprintf("id IN (SELECT issue_id FROM labels WHERE label IN (%s))", strings.Join(placeholders, ", ")))
 	}
 
+	// ID filtering: match specific issue IDs
+	if len(filter.IDs) > 0 {
+		placeholders := make([]string, len(filter.IDs))
+		for i, id := range filter.IDs {
+			placeholders[i] = "?"
+			args = append(args, id)
+		}
+		whereClauses = append(whereClauses, fmt.Sprintf("id IN (%s)", strings.Join(placeholders, ", ")))
+	}
+
 	whereSQL := ""
 	if len(whereClauses) > 0 {
 		whereSQL = "WHERE " + strings.Join(whereClauses, " AND ")