fix(tui): match execute dialog to two-toned dialog layout

[thdxr]

Summary

• Rework DialogExecute to the same title / raised-content / footer structure and theme tokens used by the existing two-toned dialogs (CommandView in dialog-integration.tsx, Answer in btw.tsx, DialogWorkspaceFileChanges)
• Outer wrapper now carries the dialog padding (<box gap={1} paddingBottom={1}>), footer trimmed to paddingLeft={2} paddingRight={2}, and the code scrollbox gains contentOptions={{ minHeight: 0 }} like the other scrollable dialogs
• Head of this: composes on the in-progress patch that wraps code/JSON by character, follows line gutters to wrapped rows, and puts the scrollable content on a raised background with its own padding

Verification

• bun typecheck in packages/tui passes
• Viewed in the live TUI via bun run dev:live at wide and narrow sizes via a temporary storybook story (removed afterward); screenshots confirm the title area, raised content band, and footer match the other two-toned dialogs

— from 𝕺𝖕𝖊𝖓𝕮𝖔𝖉𝖊