gardening: [manual-layout] replace Printf.sprintf %-*s alignment in wallets_page list panel with Grid_layout

[mathiasbourgoin]

Summary

wallets_page.ml (and the original keys_page.ml) uses Printf.sprintf "%-*s" for manual string alignment in the list panel row renderer and in address_entry_to_string for modal pickers.

This violates the HARD RULE: all TUI layouts must use Flex_layout/Grid_layout.

Files

• src/ui/pages/wallets_page.ml:481 — Printf.sprintf "%-*s" alias_width raw_alias in list panel row
• src/ui/pages/wallets_page.ml:1269-1270 — Printf.sprintf "%-14s" in modal picker address_entry_to_string

Suggested Fix

Use Grid_layout tracks with Px 20 and Fill columns for the list row rendering. The modal picker can use a fixed-width Box_widget or Flex.Px 14 column.

Pre-existing Debt

This code came from keys_page.ml which had the same issue. Not introduced by PR #784 but surfaced during review.