swarm-ui: fix WCAG contrast failures in the light-theme accent slots

argus review: the literal Catppuccin Latte accent hexes (base08-0F)
fail badly as StatusChip fill-text (green/amber/red/yellow on
--purple-dim/base03: 1.4:1-3:1, need 4.5:1) and even as plain text on
--bg/base00 in the agent/dashboard packages that also import this file
(2.3:1-4.8:1). Root cause: Latte's own accents are calibrated against
Lattes near-white base/crust, not a mid-gray surface1; the Mocha row
does not hit this because Mochas pastel accents are already light, so
they contrast fine against a dark surface1 - Lattes saturated-but-mid
accents do not have the same headroom against Lattes own lighter
surface1.

Fix: darken each accent slot from stock Latte (same hue/saturation,
lower HSL lightness via binary search) until real WCAG contrast against
base03 clears 4.5:1 with margin - verified this also clears >7:1
against base00, so both the swarm-ui chip case and the plain-text case
elsewhere are covered by one set of values. base00-07 stay stock Latte
(no contrast role, just surfaces/foreground). Yellow and peach read
closer to olive/brown than a bright yellow/orange once darkened this
far - an inherent property of darkening a warm hue in sRGB, not a
mapping mistake; boosting saturation further did not rescue it
(checked).

Verified with headless-chromium screenshots against the built swarm-ui
bundle: StatusChip text (the exact case argus flagged) and every chip
tone on /components now read clearly.

docs/web-ui/css-vars.md

@@ -18,12 +18,17 @@ for the raw `--baseNN` slots directly. (`base.css` holds only the shared
 `body` typography — it references the palette but no longer defines it.)
 
 `colors.css` ships two rows of the same 16 slots: an unconditional
-Catppuccin Mocha (dark) default, and a Catppuccin Latte (light) row gated
-behind `@media (prefers-color-scheme: light)` — both ported through the
+Catppuccin Mocha (dark) default, and a Catppuccin-Latte-derived (light)
+row gated behind `@media (prefers-color-scheme: light)` — both use the
 identical slot mapping, so which row is active never changes what a slot
-means. This is the OS/browser-level default only; it's what a client with
-no more specific theme decision gets (see "Theme swapping" below for how a
-stylix deployment or a future per-user override supersede it).
+means. The light row's `base00`-`base07` (surfaces/foreground) are stock
+Latte hexes; `base08`-`base0F` (the eight chromatic slots) are darkened
+from stock Latte to actually clear WCAG AA against how this app uses
+them (real contrast failures found in review — see the comment above
+those declarations in `colors.css` for the numbers and why). This is the
+OS/browser-level default only; it's what a client with no more specific
+theme decision gets (see "Theme swapping" below for how a stylix
+deployment or a future per-user override supersede it).
 
 Both are deliberately standalone, not `@import`ed into the page bundles:
 each package re-exports them (`src/{colors,theme}.css` →

frontend/packages/shared/src/colors.css

@@ -30,13 +30,16 @@
   --base0F: #f5c2e7; /* extra accent — pink */
 }
 
-/* Light-mode default — Catppuccin Latte, the standard light complement
-   to the Mocha defaults above, ported through the identical base16
-   slot mapping (down to the same base0C sky-over-teal substitution) so
-   a swap between the two rows never changes which semantic role a slot
-   plays. This is a *default*, not a user preference store: it only
-   applies when nothing more specific has already decided the palette.
-   A stylix-generated colors.css (nix/host-modules/hive-c0re/theme.nix)
+/* Light-mode default. base00-07 (surfaces/foreground) are stock
+   Catppuccin Latte — no contrast issue there, they're the ends of the
+   bg/fg scale. base08-0F (the eight chromatic "tone" slots: red through
+   pink) are deliberately NOT stock Latte hexes — see the comment right
+   above those declarations below for why; don't reuse stock Catppuccin
+   Latte's own accent hexes there if this ever gets regenerated.
+
+   This is a *default*, not a user preference store: it only applies
+   when nothing more specific has already decided the palette. A
+   stylix-generated colors.css (nix/host-modules/hive-c0re/theme.nix)
    replaces this entire file wholesale — a fixed, unconditional `:root`
    block with no media query in it at all — so a stylix-themed
    deployment is naturally unaffected by, and never fights, this block.
@@ -59,13 +62,38 @@
     --base05: #4c4f69; /* default foreground */
     --base06: #dc8a78; /* light foreground */
     --base07: #7287fd; /* lightest */
-    --base08: #d20f39; /* red */
-    --base09: #fe640b; /* orange / peach */
-    --base0A: #df8e1d; /* yellow */
-    --base0B: #40a02b; /* green */
-    --base0C: #04a5e5; /* cyan (our sky — note: Catppuccin's base0C is teal) */
-    --base0D: #1e66f5; /* blue */
-    --base0E: #8839ef; /* magenta / mauve */
-    --base0F: #ea76cb; /* extra accent — pink */
+    /* base08-0F: darkened from stock Catppuccin Latte's own accent
+       hexes (same hue/saturation, lower HSL lightness), not a literal
+       upstream port like base00-07 above. argus's review on this PR
+       computed real WCAG contrast ratios and found the literal Latte
+       accents fail badly as `StatusChip` fill-text (green/amber/red/
+       yellow on `--purple-dim`/base03: 1.4:1-3:1, need 4.5:1) and even
+       as plain text on `--bg`/base00 in the agent/dashboard packages
+       that also consume this same file (2.3:1-4.8:1). Root cause:
+       Latte's own accent colors are calibrated against Latte's
+       near-white `base`/`crust`, not against a mid-gray `surface1` —
+       the Mocha row doesn't have this problem because Mocha's pastel
+       accents are already *light*, so they contrast fine against a
+       *dark* surface1; Latte's saturated-but-mid-brightness accents
+       don't have the equivalent headroom against Latte's own
+       (much lighter) surface1. Each value below was picked by holding
+       the stock Latte hue+saturation fixed and binary-searching HSL
+       lightness down to the point real contrast against base03 clears
+       4.5:1 with a small margin (also verified against base00: all
+       land above 7:1 there) — same hue identity, same base16 role,
+       just dark/saturated enough to actually be legible as filled-chip
+       or plain text either way. Yellow and peach read closer to
+       olive/brown than a bright yellow/orange once darkened this far —
+       an inherent property of darkening a warm hue in sRGB (Bezold-
+       Brücke shift), not a mapping mistake; boosting saturation
+       further didn't rescue it (verified). */
+    --base08: #9c0b2a; /* red */
+    --base09: #883201; /* orange / peach */
+    --base0A: #6d450e; /* yellow */
+    --base0B: #235818; /* green */
+    --base0C: #025374; /* cyan (our sky — note: Catppuccin's base0C is teal) */
+    --base0D: #0843b8; /* blue */
+    --base0E: #6311ce; /* magenta / mauve */
+    --base0F: #8f166e; /* extra accent — pink */
   }
 }