feat(gates): WP-02 — harden check:tokens to whole-app colour guard

- Move the guard to scripts/check-tokens.sh; regex now catches hex +
  rgb()/hsl() (was hex-only) across ALL src/app components (was three
  ui/layout dirs). `token-ok` marker suppresses justified false positives;
  px stays out of scope (documented in the script).
- Zero exclusions: debug-state's dark code-editor palette moves to
  --app-devpanel-* tokens in styles.scss (the one exempt file), dropping its
  --exclude hole.
- Tokenize remaining hits: site-footer border via color-mix; three brief
  border widths via --rhc-border-width-* (new --rhc-border-width-lg: 3px).

Verified: planted violation fails the guard; GREEN + test-storybook:ci.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/app/shared/layout/site-footer/site-footer.component.ts

@@ -20,7 +20,7 @@ import { Component } from '@angular/core';
     .links a:hover{text-decoration:underline}
     /* CIBG's vendored .meta class (unrelated component, coincidental name) sets a
        dark grey — override rather than rename to keep the CIBG-mirroring class name. */
-    .meta{inline-size:100%;border-block-start:var(--rhc-border-width-sm) solid rgb(255 255 255 / 0.25);margin-block-start:var(--rhc-space-max-xl);padding-block-start:var(--rhc-space-max-lg);font-size:var(--rhc-text-font-size-sm);opacity:.85;color:var(--rhc-color-foreground-on-primary)}
+    .meta{inline-size:100%;border-block-start:var(--rhc-border-width-sm) solid color-mix(in srgb, var(--rhc-color-foreground-on-primary) 25%, transparent);margin-block-start:var(--rhc-space-max-xl);padding-block-start:var(--rhc-space-max-lg);font-size:var(--rhc-text-font-size-sm);opacity:.85;color:var(--rhc-color-foreground-on-primary)}
   `],
   template: `
     <footer class="bar">