fix(skills): every team-template skill binding now resolves

55 of 85 role skill bindings pointed at skills that were never authored,
so 10 of 11 team templates bound a smaller context bundle than their role
prompts assumed. Three roles bound nothing at all (gpu.bench_engineer,
threejs.shader_author, threejs.perf_engineer) while their prompts described
procedures they had no way to read.

The loader comment at team_template_loader.rs:167 already diagnosed this —
snake_case slugs in TOML against kebab-case skill files — and it was
half-fixed: the kebab names were corrected, the snake_case ones left.

It was invisible because both existing tests assert authored ⊆ referenced
(30/30, green) and the second explicitly declines to check the other
direction. So the failing half was the half nobody asserted.

Resolved every name by one of three explicit choices:

  - 23 skills authored where the role genuinely needed the procedure
    (gpu, threejs, research, analysis, frontend, mobile, backend, platform)
  - renames onto authored skills where one existed in substance, including
    the four-near-duplicate cases that collapse onto one real skill
  - 22 aspirational references deleted — a binding an agent cannot read is
    a promise, not a capability

Two tests now hold it. The unit test checks referenced ⊆ authored against
the files. The new integration test runs both loaders in boot order and
asserts the bindings survive the trip through the database, which is a
different question: resolution goes through skills_catalog rows, so a skill
file that exists but fails to ingest still leaves the role empty.

Negative controls: the unit test failed naming all 55; the integration test
fails naming the exact role when one name is reverted.

threejs.shader_author and .perf_engineer gained a second and third skill
after the collapse — pin_in_context pins idx < 2, so a role left with one
skill silently pins less than the policy intends.

Co-Authored-By: Claude Opus 5 <[email protected]>

skills/frontend/a11y-checklist.md

@@ -0,0 +1,51 @@
+---
+name: a11y-checklist
+description: The accessibility checks that catch most real failures, and the ones automated tools cannot make for you.
+when_to_use: You are designing or testing a UI component or screen.
+tags: [frontend, accessibility]
+---
+
+# Automated checks find about a third
+
+Run axe, then do the four manual checks it cannot do. A clean axe report on an
+unusable interface is the normal outcome, not a rare one.
+
+## The four manual checks
+
+1. **Tab through it.** Every interactive element reachable, in a sensible order,
+   with a visible focus ring. If focus disappears into an offscreen element or a
+   closed menu, the page is unusable by keyboard — the single most common real
+   failure.
+2. **Operate it without a mouse.** Open the menu, pick an item, close it with
+   Escape. Dialogs trap focus while open and return it to the trigger on close.
+3. **Zoom to 200%.** Text reflows, nothing is clipped, nothing overlaps. This is
+   also the fastest way to find fixed-height containers that will break on a
+   phone.
+4. **Read it with a screen reader once.** VoiceOver on macOS, NVDA on Windows.
+   Five minutes on the main flow finds unlabelled buttons and images whose alt
+   text reads as a filename.
+
+## What axe does catch
+
+Colour contrast, missing form labels, missing alt attributes, ARIA misuse,
+duplicate ids, heading-level jumps. Run it in CI — these regress constantly and
+are cheap to fix at the point of change.
+
+## The rules that prevent most issues
+
+- **A button is a `<button>`.** A clickable `<div>` needs role, tabindex and
+  key handlers to be equivalent, and will get at least one of them wrong.
+- **Every input has a `<label>`** with `for`, not just a placeholder. A
+  placeholder disappears on focus, which is when it was needed.
+- **Never remove the focus outline without replacing it.** `outline: none` with
+  no substitute makes keyboard use impossible. Style it instead.
+- **Icon-only buttons need an accessible name** — `aria-label`. Otherwise the
+  screen reader announces "button".
+- **Don't announce with colour alone.** A red border with no text says nothing
+  to a colourblind user or a screen reader.
+
+## Motion
+
+Honour `prefers-reduced-motion`. Vestibular disorders are common and large
+parallax or transform animations genuinely make people ill. One media query
+disables the offending animations.