feat(themes): kiln + kiln-clay — the third exclusive pair, brand new

Completes the three dark/light pairs for v1 (batch: 0ba1762, e51c8a7).
Kiln is a potter's workshop at night, lit only by the kiln: warm
near-black (#1D1815), copper accent (#D68C5C, 6.5:1), brass accentAlt,
CaskaydiaCove, rounding 8. Kiln Clay is the same studio at midday:
cream plaster (#F4EDE3), espresso text (11.1:1 AAA), fired-copper
accent (#A34F1F, 4.89:1), brick-red bad. Both waybars are a NEW
whole-swap identity — 'the workbench': ONE continuous floating plank
(window#waybar carries the surface, modules transparent) — deliberately
distinct from boreal's three pills and slate's edge-to-edge strip;
module set verbatim-parity with the generated config. Matched rofi,
btop themes. The wallpapers share identical ring geometry — banked-coal
heat rings at night, terracotta glaze rings at noon — so the autoTheme
flip visibly rhymes.

Sync sweep in this commit (LOOP §5): README 24->28 presets + the
whole-swap list now names the three pairs; CONVENTIONS waybar parity
list gains the four new slugs; OVERRIDES autoTheme table points at the
pairs; HARDWARE-QUEUE gains the batch V3 entry (real-GL blur, btop
visual, launcher grid, tray menus, pair flip); BACKLOG files #153
(PROPOSED: per-theme desktop widgets — the conky idea, engine spike
needed, not v1).

Verification: V2. Full targeted set green on the final tree:
theme-contrast, theme-wholeswap (previews + backgrounds + CSS
self-containment), waybar-language, waybar-swap-env, rofi-text-width,
state-sync-validate, auto-theme VM; nix flake check --no-build green.
Visual protocol: theme-shot VM desktop + menu viewed for BOTH themes
(plank renders as one island, copper/terracotta semantics, legible
menus; /nix/store/2fizd945...theme-shot-kiln and
/nix/store/0126yd48...theme-shot-kiln-clay). audit-theme-design:
CVD-only findings (≤ executive-slate's own baseline); ANSI slots
in-family after the magenta retune. V3 pending: HARDWARE-QUEUE entry
above. btop visual is VM-blocked (GL terminal never starts under
softGL) — file-level assertions only, listed for hardware.

Design + wallpapers on Fable; assets by a Sonnet subagent to a written
identity spec; reviewed on Fable.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

themes/kiln/rofi.rasi

@@ -0,0 +1,121 @@
+/**
+ * Kiln — rofi whole-swap (themes/<slug>/rofi.rasi).
+ * The base theme: a solid warm clay panel lit by ember-copper edge glow —
+ * no frost, no glass, a potter's workbench at night. Element structure
+ * mirrors the generated theme so the theme-grid picker's per-invocation
+ * -theme-str still lays out. The `configuration {}` block is omitted on
+ * purpose — it comes from modules/home/rofi.nix.
+ */
+
+* {
+    base:       #1D1815;
+    panelBg:    #1D1815F2;
+    surface:    #2C241E;
+    overlay:    #41362D;
+    text:       #EADFD3;
+    subtext:    #B5A695;
+    muted:      #77685A;
+    accent:     #D68C5C;
+    accentAlt:  #C8A94E;
+    accentEdge: #D68C5C66;
+    accentWash: #D68C5C33;
+
+    font: "CaskaydiaCove Nerd Font 11";
+    background-color: transparent;
+    text-color: @text;
+}
+
+window {
+    background-color: @panelBg;
+    border: 1px;
+    border-color: @accentEdge;
+    border-radius: 8px;
+    width: calc( 84ch min 65% );
+    location: center;
+    anchor: center;
+    padding: 16px;
+}
+
+mainbox {
+    background-color: transparent;
+    children: [ inputbar, message, listview ];
+    spacing: 12px;
+}
+
+inputbar {
+    children: [ prompt, entry ];
+    background-color: @surface;
+    text-color: @text;
+    border-radius: 8px;
+    padding: 12px 16px;
+    spacing: 10px;
+}
+
+prompt { text-color: @accent; }
+
+entry {
+    text-color: @text;
+    cursor: text;
+    placeholder: "Search…";
+    placeholder-color: @muted;
+}
+
+listview {
+    background-color: transparent;
+    columns: 1;
+    lines: 8;
+    dynamic: true;
+    scrollbar: true;
+    spacing: 6px;
+    padding: 4px 0px 0px 0px;
+}
+
+element {
+    background-color: transparent;
+    text-color: @text;
+    orientation: horizontal;
+    border-radius: 8px;
+    padding: 10px 14px;
+    spacing: 12px;
+}
+
+element normal.normal,
+element alternate.normal {
+    background-color: transparent;
+}
+
+/* Selected row lifts on a soft ember-copper wash. */
+element selected.normal {
+    background-color: @accentWash;
+    text-color: @text;
+}
+
+element-icon {
+    background-color: transparent;
+    size: 30px;
+    cursor: inherit;
+}
+
+element-text {
+    background-color: transparent;
+    text-color: inherit;
+    highlight: bold;
+    vertical-align: 0.5;
+}
+
+message { padding: 0px; }
+
+textbox {
+    background-color: @surface;
+    text-color: @text;
+    border-radius: 8px;
+    padding: 10px 14px;
+}
+
+scrollbar {
+    width: 4px;
+    handle-width: 4px;
+    handle-color: @accent;
+    background-color: @surface;
+    border: 0px;
+}