Implement visual accommodations and Full Keyboard Access

Full relative text scaling per DESIGN/10: BoardMetrics is the board
strip's geometry as a pure function of the body point size
(CardWindowMetrics' twin) — lane plate/header/band, card
corner/stripe/padding, masonry spacing, the drop model's nominal card
height, resize-handle geometry, trash hatch pitch, and both window
floors all derive from an em; CardFaceMetrics folded in. The two fixed
font sizes (welcome brand/glyph) went relative; the toolbar search
field is 17 ems like the transient bar's. The no-horizontal-scroll
invariant is pinned by test at six text sizes by twelve lane counts.

Accommodations is Motion's sibling for the visual settings: Increase
Contrast adds a flat point to strokes (monotone, hierarchy-preserving),
gives borderless card/lane plates a resting separator hairline, and
takes faded accents to full alpha; Reduce Transparency turns the
transient search bar's glass solid and does the same for the alpha
washes that composite over a user-chosen board background (trash plate,
hatched header, drag shadow). Reduce Motion audited — every animated
surface already routes through Motion with a reduced variant; no gaps.

Full Keyboard Access: the template chooser's tiles were pointer-only —
now focusable, arrow-navigable (clamped, StyleWellGrid's rule), Space
picks, Return stays the sheet's default action, focus names the
selection one-way. The board's single tab stop shows its focus ring
under FKA (focusEffectDisabled inverts). Style editor verified already
conformant. Edge accents verified text-free; trash hatch pitch now
font-derived so it still reads as hatching at large text.

1549 unit tests green, both schemes build.

Claude-Session: https://claude.ai/code/session_01SR4XGjmBE16ZUYWpfFHXwY

Kanban/App/WelcomeView.swift

@@ -38,6 +38,20 @@ struct WelcomeView: View {
     /// Whether the recents list holds the keyboard, so Return can mean "open the selected row".
     @FocusState private var listFocused: Bool
 
+    // MARK: - Geometry
+    //
+    // Every figure this window lays out on, as a multiple of the body font — `BoardMetrics`' rule
+    // applied to the welcome window (10-accessibility.md ▸ Text scaling & visual accommodations). At
+    // the standard 13pt body they reproduce the numbers welcome has always drawn.
+
+    @MainActor static var pointSize: CGFloat { BoardMetrics.bodyPointSize }
+
+    @MainActor static var brandingColumnWidth: CGFloat { BoardMetrics.em(23, bodyPointSize: pointSize) }
+    @MainActor static var brandingInset: CGFloat { BoardMetrics.em(2.5, bodyPointSize: pointSize) }
+    @MainActor static var appIconSide: CGFloat { BoardMetrics.em(7.4, bodyPointSize: pointSize) }
+    @MainActor static var minimumWidth: CGFloat { BoardMetrics.em(58.5, bodyPointSize: pointSize) }
+    @MainActor static var minimumHeight: CGFloat { BoardMetrics.em(35.4, bodyPointSize: pointSize) }
+
     private var derivation: WelcomeRow.Derivation {
         WelcomeRow.derive(recents: appModel.recents, failures: appModel.launchFailures)
     }
@@ -49,16 +63,20 @@ struct WelcomeView: View {
     var body: some View {
         HStack(spacing: 0) {
             branding
-                .frame(width: 300)
+                .frame(width: Self.brandingColumnWidth)
                 .frame(maxHeight: .infinity)
-                .padding(32)
+                .padding(Self.brandingInset)
 
             Divider()
 
             recents
                 .frame(maxWidth: .infinity, maxHeight: .infinity)
         }
-        .frame(minWidth: 760, minHeight: 460)
+        // Font-derived, like the board window's floor (10-accessibility.md ▸ Text scaling: "no fixed
+        // point sizes"): at a large system text size a 300-point branding column would clip the app
+        // name it exists to show, and a 760 × 460 floor would leave the recents list too narrow for
+        // the three lines each row carries. At the standard body size these are those numbers.
+        .frame(minWidth: Self.minimumWidth, minHeight: Self.minimumHeight)
         // The window has no title bar, so the background is the drag handle. `.gesture` rather than
         // `.highPriorityGesture`: a click on a row or a button belongs to the row or the button.
         .gesture(WindowDragGesture())
@@ -76,12 +94,16 @@ struct WelcomeView: View {
         VStack(alignment: .leading, spacing: 0) {
             Image(nsImage: NSApp.applicationIconImage)
                 .resizable()
-                .frame(width: 96, height: 96)
+                .frame(width: Self.appIconSide, height: Self.appIconSide)
                 .accessibilityHidden(true)
 
             Text("Lanework")
-                .font(.system(size: 34, weight: .light))
-                .padding(.top, 12)
+                // A **relative** style, not a 34pt literal — "relative text styles everywhere, no
+                // fixed point sizes" (10-accessibility.md ▸ Text scaling & visual accommodations).
+                // `.largeTitle` is the app name's register and it grows with the system text size;
+                // a fixed size would have stayed put while every line beneath it grew past it.
+                .font(.largeTitle.weight(.light))
+                .padding(.top, BoardMetrics.em(0.9, bodyPointSize: Self.pointSize))
 
             Text(versionSummary)
                 .font(.callout)
@@ -90,11 +112,11 @@ struct WelcomeView: View {
             Text("Folders and Markdown, on your terms.")
                 .font(.caption)
                 .foregroundStyle(.tertiary)
-                .padding(.top, 4)
+                .padding(.top, BoardMetrics.em(0.3, bodyPointSize: Self.pointSize))
 
-            Spacer(minLength: 24)
+            Spacer(minLength: BoardMetrics.em(1.85, bodyPointSize: Self.pointSize))
 
-            VStack(spacing: 8) {
+            VStack(spacing: BoardMetrics.em(0.6, bodyPointSize: Self.pointSize)) {
                 // The menu-bar twin of this button is File ▸ New Board… (⌥⌘N) — same action, and
                 // deliberately the same words, because a button and a menu item that differ read as
                 // two features.
@@ -216,7 +238,7 @@ struct WelcomeView: View {
             }
             .controlSize(.small)
         }
-        .padding(16)
+        .padding(BoardMetrics.em(1.25, bodyPointSize: Self.pointSize))
         .frame(maxWidth: .infinity, alignment: .leading)
     }
 
@@ -249,7 +271,7 @@ private struct WelcomeActionButton: View {
         Button(action: action) {
             Label(title, systemImage: systemImage)
                 .frame(maxWidth: .infinity, alignment: .leading)
-                .padding(.vertical, 2)
+                .padding(.vertical, BoardMetrics.em(0.15, bodyPointSize: WelcomeView.pointSize))
         }
         .buttonStyle(.bordered)
         .controlSize(.large)
@@ -271,9 +293,13 @@ private struct RecentBoardRow: View {
             // lenient-fallback shape every other icon site in the app uses (`ItemSymbol`,
             // `Palette`), applied here to the registry's cached string instead of a live snapshot.
             Image(systemName: iconName)
-                .font(.system(size: 22))
+                // Relative, like every other size in this window (10-accessibility.md's
+                // full-relative-scaling rule): `.title` is the register a 22pt glyph occupied at the
+                // standard text size, and the well around it is derived from the body font so the
+                // glyph never outgrows it.
+                .font(.title)
                 .foregroundStyle(iconTint)
-                .frame(width: 34, height: 34)
+                .frame(width: iconWell, height: iconWell)
                 .accessibilityHidden(true)
 
             VStack(alignment: .leading, spacing: 1) {
@@ -292,13 +318,19 @@ private struct RecentBoardRow: View {
 
             Spacer(minLength: 0)
         }
-        .padding(.vertical, 4)
+        .padding(.vertical, BoardMetrics.em(0.3, bodyPointSize: WelcomeView.pointSize))
         // Dimmed when the board cannot be reached — the row stays, with Forget, rather than
         // disappearing (02 § Graceful orphaning).
         .opacity(row.isAvailable ? 1 : 0.55)
         .accessibilityElement(children: .combine)
     }
 
+    /// The square the row's glyph sits in — font-derived so the icon column stays proportionate to
+    /// the three lines of text beside it at every system text size.
+    private var iconWell: CGFloat {
+        BoardMetrics.em(2.6, bodyPointSize: BoardMetrics.bodyPointSize)
+    }
+
     /// `row.icon`'s symbol if it names one this system can draw, the board default otherwise —
     /// `ItemSymbol.name(_:fallback:)`'s rule, restated for a plain cached string rather than a
     /// `FieldValue`: a record carries no `FieldValue`, so `missing`/`malformed`/`unrecognized`
@@ -365,7 +397,10 @@ struct SettingsView: View {
             }
         }
         .formStyle(.grouped)
-        .frame(width: 420)
+        // Font-derived: this pane is `.fixedSize()`, so a 420-point literal would clip its one
+        // toggle's footer sentence at a large system text size with no way to resize out of it
+        // (10-accessibility.md ▸ Text scaling).
+        .frame(width: BoardMetrics.em(32.3, bodyPointSize: BoardMetrics.bodyPointSize))
         .fixedSize()
     }
 }