feat(blocks): add SkillList for review desk catalog

Static markup-only component for the review desk's left-column listbox.
Renders one button per entry with the four-row template (author, title,
skill/status, package summary) and applies the 'active' class for the
currently-selected entry. Click handling and URL sync are task 16.

Preserves every CSS hook asserted by scripts/verify.mjs:
#skill-list, .active, grid-template-columns:minmax(0,1fr), height:120px,
-webkit-line-clamp:2. Visual fidelity gaps (panel surface tints) listed
in the task report.

Did not: extract per-row components (catalog is data, not markup);
introduce client: directives (interactivity is task 16); add new tokens
(design-system-keeper's job).

src/components/blocks/SkillList.astro

@@ -0,0 +1,151 @@
+---
+// SkillList — the catalog listbox of reviewed submissions.
+//
+// The 24 reviews are data, not 24 components. One list, one row template.
+// Click handling and selection state are task 16's job; this component
+// ships zero JS and just renders the rows from props.
+//
+// The id `#skill-list` and CSS class `active` are asserted by
+// scripts/verify.mjs via the legacy stylesheet. They survive here so the
+// verification engineer can re-point assertions at the new architecture
+// without renaming anything. CSS hooks `grid-template-columns:minmax(0,1fr)`,
+// `height:120px`, and `-webkit-line-clamp:2` are kept verbatim for the same
+// reason — task 19 will diff against this baseline.
+
+interface SkillEntry {
+  /** Stable identifier used for selection and URL params. */
+  id: string;
+  /** Display name of the submitter. */
+  author: string;
+  /** Skill title — second row of the row template. */
+  title: string;
+  /** Short status string ("reviewed", "draft", etc.). */
+  status: string;
+  /** Pre-computed package summary (e.g. "1 skill · 2 refs · 1 script"). */
+  summary: string;
+}
+
+interface Props {
+  entries: SkillEntry[];
+  /** Optional id of the currently-selected entry; the matching row gets
+   *  `aria-selected="true"` and the `active` class. */
+  selectedId?: string;
+}
+
+const { entries, selectedId } = Astro.props;
+---
+
+<div id="skill-list" role="listbox" aria-label="Submitted skills">
+  {
+    entries.map((entry) => (
+      <button
+        type="button"
+        role="option"
+        aria-selected={entry.id === selectedId}
+        class={entry.id === selectedId ? 'active' : ''}
+        data-id={entry.id}
+      >
+        <span>AUTHOR · {entry.author}</span>
+        <strong>{entry.title}</strong>
+        <small>
+          SKILL · {entry.id} · {entry.status}
+        </small>
+        <em>{entry.summary}</em>
+      </button>
+    ))
+  }
+</div>
+
+<style>
+  /* The listbox grid: one column, four rows. The fixed height + ellipsis
+     is what keeps 24 rows scannable; this is the row template. */
+  #skill-list {
+    display: grid;
+    gap: 1px;
+    border-top: 1px solid var(--line);
+  }
+
+  #skill-list button {
+    display: grid;
+    grid-template-columns: minmax(0, 1fr);
+    grid-template-rows: 14px 36px 13px 13px;
+    gap: 4px;
+    height: 120px;
+    overflow: hidden;
+    padding: 14px;
+    border: 0;
+    border-bottom: 1px solid var(--line);
+    color: var(--ink);
+    background: transparent;
+    text-align: left;
+    cursor: pointer;
+  }
+
+  /* Author line: top eyebrow. Truncates to a single line. */
+  #skill-list button span {
+    color: var(--muted);
+    font: 10px monospace;
+    overflow: hidden;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+  }
+
+  /* Title: two-line clamp so a long title doesn't push other rows. */
+  #skill-list button strong {
+    font-size: var(--step-1);
+    line-height: 18px;
+    max-height: 36px;
+    overflow: hidden;
+    display: -webkit-box;
+    -webkit-box-orient: vertical;
+    -webkit-line-clamp: 2;
+    overflow-wrap: anywhere;
+  }
+
+  /* SKILL · status: short status line. */
+  #skill-list button small {
+    display: block;
+    color: var(--red);
+    font: 9px monospace;
+    text-transform: uppercase;
+    max-height: 13px;
+    line-height: 13px;
+    overflow: hidden;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+  }
+
+  /* Package summary: monospace, single line. */
+  #skill-list button em {
+    display: block;
+    max-height: 13px;
+    overflow: hidden;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+    line-height: 13px;
+    /* --blue on the surface; the active-state tone has no canonical token
+       and uses --gold as the closest fallback (legacy palette gap). */
+    color: var(--blue);
+    font:
+      var(--step-0) / 13px ui-monospace,
+      monospace;
+    font-style: normal;
+  }
+
+  /* Hover and selected states flip the row to the dark surface. */
+  #skill-list button:hover,
+  #skill-list button.active {
+    color: var(--paper);
+    background: var(--ink);
+  }
+
+  #skill-list button.active span,
+  #skill-list button.active small {
+    color: var(--gold);
+  }
+
+  #skill-list button:focus-visible {
+    outline: 3px solid var(--red);
+    outline-offset: 2px;
+  }
+</style>