feat(quickshell): cap the rail's open chamfers and trace between them

A chamfer with no neighbour behind it now carries the corner it removed,
put back OUTSIDE the panel as a detached accent triangle. capGap is the
perpendicular distance from the cut, hence the per-axis shift of capGap
over root 2: the cap moves along the cut's normal, not along an axis.

The trace joining two caps belongs to the RAIL, not the panel — the run it
draws is the gap BETWEEN two panels, which no panel can see. HyprChromeBar
filters the row down to panels (a slack Item has no `rightChamfer`, so
spacers drop out, and dropping them is exactly what makes a trace span
them), then joins each right cap to the next left cap: straight, one 45°
step at the midpoint of the gap, straight. It meets the middle of each
cap's outward face rather than its tip.

TestPanel is a staging slot between two spacers. It counts seconds since
load, which is the cheapest proof the panel is live, and standing alone it
exercises a cap and a trace at both ends — something a rail of butted
panels never does.

Restructures the module in the same commit, since the moves and the edits
above land in the same files: folders are PascalCase, the bar and its
widgets moved under Widgets/Bar, and DebugWindow takes the HyprChrome Theme
instead of the legacy one. The two singletons are identical today, so that
is not a visual fix — it is a palette edit reaching the debug stage in
future. Rename detection needs -M40% to follow HyprChromeBar, which grew
past the default similarity threshold.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01U19X5LGTxtq4pb4jdNVivv

dotfiles/quickshell/HyprChrome/Theme/Theme.qml

@@ -0,0 +1,61 @@
+pragma Singleton
+
+import Quickshell
+import QtQuick
+
+// Single source of truth for the shell's palette and font families.
+//
+// The shell previously ran two unrelated palettes: an amber one (#FFD063) used
+// by the launchers, sidebar, systray, vitals and notifications, and an orange
+// one (#e8722a) that only the dense bar had, tokenized as per-file properties.
+// This unifies on the ORANGE values under the AMBER naming scheme.
+//
+// `surface` deliberately takes the dense bar's void (#0a0a0a) rather than the
+// old panel background (#0F1012), which also absorbs the near-identical
+// #0A0A0C scrim.
+Singleton {
+    // ---- core ----
+    readonly property color accent: "#e8722a"   // was #FFD063 (amber) / #e8722a (bar)
+    readonly property color text: "#dedede"     // was #EEEEEE / #dedede
+    readonly property color muted: "#858585"    // was #7A7B7D / #858585
+    readonly property color surface: "#0a0a0a"  // was #0F1012 + #0A0A0C + #0a0a0a
+    readonly property color hot: "#ff6b4a"      // alert/hot; no bar equivalent, kept
+
+    // ---- supporting darks ----
+    // A three-step ramp above `surface`. `raised` also absorbs #22262C, which
+    // differed from #292C30 by an imperceptible amount across two call sites.
+    readonly property color selection: "#1a1c1f"  // selected row fill
+    readonly property color raised: "#292c30"     // raised surface / border
+    readonly property color disabled: "#3a3d42"   // unknown / disabled stroke
+
+    // ---- accents ----
+    // The pale "flash" the top/bottom bars show while a launcher is open. Was a
+    // hand-picked #FFF3C0 against amber; derived here so it tracks `accent`.
+    // 55% toward white reproduces the original amber relationship closely
+    // (#FFD063 -> #FFE9B8 vs the hand-picked #FFF3C0).
+    readonly property color accentSoft: Qt.tint(accent, Qt.rgba(1, 1, 1, 0.55))
+    readonly property color highlight: "#ffffff"
+
+    // ---- fonts ----
+    // Two faces. `readoutFont` is an alias rather than a second literal so the
+    // two roles cannot silently drift apart; point it at a different family if
+    // the readouts should ever diverge from the headings again.
+    //
+    // Installed by services/desktop/desktop-apps.nix (nerd-fonts.departure-mono).
+    // The former readout face, Digital-7 Mono, was never packaged — it relied on
+    // a manual ~/.dots/fonts/digital_7 install, so dropping it also removes an
+    // undeclared external dependency.
+    readonly property string displayFont: "DepartureMono Nerd Font" // headings, large values
+    readonly property string readoutFont: displayFont               // seven-segment readouts: launchers, sidebar, systray, vitals
+    readonly property string microFont: "DejaVu Sans Mono"          // dense bar micro labels
+
+    // ---- derived alpha variants ----
+    // The dense bar hand-encoded these as Qt.rgba(0.87,0.87,0.87,a) = text and
+    // Qt.rgba(0.91,0.45,0.16,a) = accent. Expressed as functions so the
+    // relationship survives a palette change.
+    function textAlpha(a) { return Qt.rgba(text.r, text.g, text.b, a); }
+    function accentAlpha(a) { return Qt.rgba(accent.r, accent.g, accent.b, a); }
+
+    // Hairline rule / panel outline: text at 28%.
+    readonly property color hair: textAlpha(0.28)
+}