feat: add reviews content collection

Move all 24 review entries from skills-review/catalog.js +
skills-review/submitted-catalog.js into a typed Astro content collection at
src/content/reviews/. Each entry is a Markdown file with frontmatter for the
review metadata (id, author, focus, wins, improve, extras, name, description)
and a body that holds the 'improved' SKILL.md content.

Re-point scripts/build-skill-review.mjs at the new collection. The generator
reads each .md file, parses its YAML frontmatter, and writes
skill-reviews/improved/{id}/SKILL.md in the same shape the legacy catalog
produced — verified byte-identical via 'git diff --exit-code skill-reviews/'.

The 'name' field is preserved separately from 'id' because two entries
renamed the skill during review (id angular-accessibility-root → name
angular-accessibility; id confectionary-skill-hub → name confectionery-orders).
Without it the generator output would drift on those two files.

Does not yet delete skills-review/catalog.js or submitted-catalog.js —
verify.mjs and the legacy review-desk page both still read them, so they
stay as a mirror until task 16 rewires the page to the collection. Adding a
new submission today requires editing both the .md file (new source of
truth) and the legacy catalog.js (until task 16).

Done-when:
- 24 entries under src/content/reviews/ ✓
- verify.mjs's id:' count assertion still passes ✓
- git diff --exit-code skill-reviews/ clean after regenerating ✓
- astro check passes (22 files: 0 errors, 0 warnings, 2 hints) ✓

Co-Authored-By: Claude Code <noreply@anthropic.com>

src/content/reviews/sql-injection-audit.md

@@ -0,0 +1,53 @@
+---
+author: 'Andre Salvo'
+description:
+  'Audit a changed code path for SQL injection. Use when code constructs or
+  executes SQL, query-builder fragments, or ORM raw queries.'
+extras:
+  'Add an eval with a parameterized query and a dynamic `ORDER BY` allowlist.'
+focus:
+  'Trace user-controlled data to SQL sinks and verify values are parameterized.'
+id: 'sql-injection-audit'
+improve:
+  - 'The frontmatter is invalid because an un-keyed line appears inside it; fix
+    this first so hosts can discover the skill.'
+  - 'Scope the audit to changed code or named paths by default to avoid an
+    unbounded repository scan.'
+  - 'Add language-specific safe/unsafe examples in a reference rather than
+    expanding the main file.'
+name: 'sql-injection-audit'
+path: '../submitted-skills/Andre%20Salvo/skills/sql-injection-audit/SKILL.md'
+status: 'Fix metadata'
+title: 'SQL injection audit'
+wins:
+  - 'Strong threat-model coverage, including identifiers and second-order
+    injection.'
+  - 'The report asks for source, sink, and data flow.'
+---
+
+# sql-injection-audit
+
+## Inputs
+
+Changed files, branch diff, or a named query path.
+
+## Workflow
+
+1. Find SQL execution sinks and trace request, CLI, external, and stored user
+   input to them.
+2. Confirm values use driver or ORM parameters. For dynamic identifiers, confirm
+   a finite allowlist maps a user choice to a trusted token.
+3. Review raw-query escape hatches and stored procedures.
+4. Report only evidenced findings with source, sink, location, impact, and a
+   safe pattern.
+
+## Rules
+
+- Escaping is not a substitute for parameterization.
+- Passing tests are supporting evidence, not proof of safety.
+- Do not modify code unless the user asks for a fix.
+
+## Output
+
+Return a findings table and the scope reviewed; say explicitly when a path could
+not be traced.