Fix TUI details viewport scrolling

apps/tui/COMMANDS.md

@@ -19,7 +19,7 @@ Secret-bearing commands are masked and omitted from history.
 | --- | --- | --- |
 | Global | `?`, `:`, `C-l`/`C-z`, `q` | help, command prompt, secure lock, quit |
 | Tree | `j`/`k`, arrows, `h`/`l`, `Enter`, `/`, `n`/`N` | move, collapse/expand, open, filter, cycle matches |
-| Entry | `Tab`/`Shift-Tab`, `v`/`V`, `y`, `e`, `Esc` | focus, reveal/hide, timed copy, edit, close |
+| Entry | `j`/`k`, arrows, `Tab`/`Shift-Tab`, `v`/`V`, `y`, `e`, `Esc` | focus, reveal/hide, timed copy, edit, close |
 | Editor | `i`, `a`, `d`, `K`/`J`, `g`, `C-s` | edit/add/remove/reorder/generate/save fields |
 | Store | `I`, `i`, `p`, `\\`, `d d`, `m`, `c` | init, insert, generate, grep, remove, move, copy |
 | Git | `g p`, `g P` | pull, push; all other Git operations use `:git …` |
@@ -87,6 +87,9 @@ renders five-row digit-only glyphs and a storage-period-driven countdown bar.
 Shorter panes fall back to a leading inline code and remaining-seconds label.
 The displayed TOTP survives field navigation, refreshes at its exact storage
 boundary, and is removed when the entry closes or the application relocks.
+The details viewport remains fixed while the focused field is visible. It moves
+by the minimum number of rows only when field navigation crosses an edge, and
+recalculates that visibility after terminal and OTP layout changes.
 
 `:quit` is a TUI convenience. Shell-completion script generation is a CLI
 build-time/integration surface; interactive Tab completion replaces it here.