fix(design): text on a tint of itself now clears AA app-wide, and the check gates it (#3141)

The badge fix (#3132) exposed the same defect everywhere: 48 rules painting a
token as TEXT on an inline color-mix tint of that same token. Worst raw
measurements, across every tint strength in use, both modes, over
page/raised/hover:

  accent 1.53:1 · success 1.67:1 · text-tertiary 2.15:1
  warning 2.32:1 · error 2.36:1                        against AA's 4.5

THE DEFECT IS IN THE HOUSE, NOT IN SCRIBE. The semantic hues are shared
family-wide, and the accent case was measured against every app's real
accent, not assumed from Scribe's: Minstrel 1.81, Forge 1.87, Steward 1.65,
Roundtable 3.01 — all failing. So the six -fg tokens are recorded on
FabledSword (design system 1), where their parents live, rather than copied
into each app.

45% toward --fs-text-primary clears AA for ALL FIVE accents (4.56-5.00), so
this is one house token rather than five overrides, and it keeps deriving
from --fs-accent — an app that overrides its accent still gets a legible
tinted-text colour in its own colour, the same mechanism as
--fs-accent-soft. The tokens are additive: a sibling app is unaffected until
it regenerates its own stylesheet.

One token is honestly redundant. --fs-text-secondary already passes at
4.82:1, and --fs-text-secondary-fg barely moves it. It exists so the rule
has NO exceptions, because the alternative is a permanent allow-list entry
for the one case that happens to pass — and a guard with an invisible
exception is a guard that erodes.

46 substitutions across 18 files, each rewriting only the `color:` inside a
block that tints its own background.

THE CHECK NOW GATES BOTH SPELLINGS. It previously reported the inline form,
because a gate nobody can satisfy on the day it lands gets switched off.
Both are clean, so both fail the build now.

And the check had a false-positive bug worth naming: its `color\s*:` regex
matched the tail of `border-color`, `border-left-color` and `outline-color`,
so it flagged seven rules that were already correct. A border is a non-text
graphic with a 3:1 floor, not text at 4.5. A check that cries wolf on
correct code is one that gets muted, so that mattered more than the noise.

Verified by construction, not by passing: reintroduced each defect form
(exit 1 each), and confirmed a legitimate border-only rule still exits 0.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

frontend/src/components/AppHeader.vue

@@ -206,7 +206,7 @@ router.afterEach(() => {
   background: var(--fs-accent-soft);
 }
 .nav-link.router-link-active {
-  color: var(--fs-accent);
+  color: var(--fs-accent-fg);
   font-weight: 500;
   background: color-mix(in srgb, var(--fs-accent) 25%, transparent);
   box-shadow: 0 0 16px color-mix(in srgb, var(--fs-accent) 30%, transparent);
@@ -257,7 +257,7 @@ router.afterEach(() => {
   font-weight: 500;
   text-transform: uppercase;
   letter-spacing: 0.05em;
-  color: var(--fs-accent);
+  color: var(--fs-accent-fg);
   background: color-mix(in srgb, var(--fs-accent) 15%, transparent);
   padding: 0.1rem 0.35rem;
   border-radius: var(--fs-radius-sm);

frontend/src/components/DiffView.vue

@@ -137,12 +137,12 @@ function markerFor(type: DiffLine['type']): string {
 
 .diff-delete {
   background: color-mix(in srgb, var(--fs-error) 12%, transparent);
-  color: var(--fs-error);
+  color: var(--fs-error-fg);
 }
 
 .diff-insert {
   background: color-mix(in srgb, var(--fs-success) 12%, transparent);
-  color: var(--fs-success);
+  color: var(--fs-success-fg);
 }
 
 .diff-equal {

frontend/src/components/InlineAssistPanel.vue

@@ -227,11 +227,11 @@ const markers: Record<DiffLine["type"], string> = {
 .iap-diff-equal  { color: var(--fs-text-tertiary); }
 .iap-diff-delete {
   background: color-mix(in srgb, var(--fs-error) 10%, transparent);
-  color: var(--fs-error);
+  color: var(--fs-error-fg);
 }
 .iap-diff-insert {
   background: color-mix(in srgb, var(--fs-success) 10%, transparent);
-  color: var(--fs-success);
+  color: var(--fs-success-fg);
 }
 
 .iap-diff-marker {

frontend/src/components/MarkdownToolbar.vue

@@ -156,7 +156,7 @@ const groups = [
 
 .md-btn.active {
   background: color-mix(in srgb, var(--fs-accent) 14%, transparent);
-  color: var(--fs-accent);
+  color: var(--fs-accent-fg);
   box-shadow: 0 0 0 1px color-mix(in srgb, var(--fs-accent) 35%, transparent);
 }
 

frontend/src/components/SystemsSection.vue

@@ -679,7 +679,7 @@ async function confirmDelete() {
   font-weight: 500;
   background: color-mix(in srgb, var(--fs-accent) 12%, transparent);
   border: 1px solid color-mix(in srgb, var(--fs-accent) 30%, transparent);
-  color: var(--fs-accent);
+  color: var(--fs-accent-fg);
   border-radius: 999px;
   padding: 0.05rem 0.45rem;
   flex-shrink: 0;
@@ -689,7 +689,7 @@ async function confirmDelete() {
   font-weight: 500;
   text-transform: uppercase;
   letter-spacing: 0.04em;
-  color: var(--fs-text-tertiary);
+  color: var(--fs-text-tertiary-fg);
   background: color-mix(in srgb, var(--fs-text-tertiary) 12%, transparent);
   border-radius: 999px;
   padding: 0.05rem 0.45rem;

frontend/src/components/TagInput.vue

@@ -168,7 +168,7 @@ function focusInput() {
   border-radius: 999px;
   background: color-mix(in srgb, var(--fs-accent) 15%, transparent);
   border: 1px solid var(--fs-accent);
-  color: var(--fs-accent);
+  color: var(--fs-accent-fg);
   font-size: 0.8rem;
   white-space: nowrap;
 }

frontend/src/components/WorkspaceNoteEditor.vue

@@ -548,7 +548,7 @@ defineExpose({ reload: loadProjectNotes });
 
 .note-tag-pill {
   font-size: 0.58rem;
-  color: var(--fs-accent);
+  color: var(--fs-accent-fg);
   background: color-mix(in srgb, var(--fs-accent) 10%, transparent);
   border-radius: 999px;
   padding: 0 0.3rem;
@@ -645,7 +645,7 @@ defineExpose({ reload: loadProjectNotes });
 .btn-tag-suggestion.applied {
   background: color-mix(in srgb, var(--fs-accent) 15%, transparent);
   border-color: var(--fs-accent);
-  color: var(--fs-accent);
+  color: var(--fs-accent-fg);
 }
 
 .link-suggest-strip {

frontend/src/components/WorkspaceTaskPanel.vue

@@ -424,8 +424,8 @@ defineExpose({ reload: loadAll });
   border-radius: 10px;
   text-transform: capitalize;
 }
-.ms-status-active { background: color-mix(in srgb, var(--fs-accent) 15%, transparent); color: var(--fs-accent); }
-.ms-status-completed { background: color-mix(in srgb, var(--fs-success) 15%, transparent); color: var(--fs-success); }
+.ms-status-active { background: color-mix(in srgb, var(--fs-accent) 15%, transparent); color: var(--fs-accent-fg); }
+.ms-status-completed { background: color-mix(in srgb, var(--fs-success) 15%, transparent); color: var(--fs-success-fg); }
 
 .task-items {
   list-style: none;
@@ -516,8 +516,8 @@ defineExpose({ reload: loadAll });
   user-select: none;
   margin-left: auto;
 }
-.status-cycler.status-in_progress { border-color: var(--fs-accent); color: var(--fs-accent); background: color-mix(in srgb, var(--fs-accent) 10%, transparent); }
-.status-cycler.status-done { border-color: var(--fs-success); color: var(--fs-success); background: color-mix(in srgb, var(--fs-success) 10%, transparent); }
+.status-cycler.status-in_progress { border-color: var(--fs-accent); color: var(--fs-accent-fg); background: color-mix(in srgb, var(--fs-accent) 10%, transparent); }
+.status-cycler.status-done { border-color: var(--fs-success); color: var(--fs-success-fg); background: color-mix(in srgb, var(--fs-success) 10%, transparent); }
 
 .btn-edit-task { margin-left: 0.25rem; }
 .btn-edit-task:hover { text-decoration: underline; }