fix: strip frontmatter from injected skill content and share parser from src

scripts/generate.ts

@@ -10,10 +10,18 @@
 //
 // Deterministic: same inputs produce byte-identical outputs, so the nightly git diff is the
 // affected-set report. Never hand-edit skills/ or the matrix section.
-import { cpSync, existsSync, readFileSync, readdirSync, rmSync, statSync, writeFileSync } from "node:fs"
+import {
+  cpSync,
+  existsSync,
+  readFileSync,
+  readdirSync,
+  rmSync,
+  statSync,
+  writeFileSync,
+} from "node:fs"
 import path from "node:path"
 import { fileURLToPath } from "node:url"
-import { isUserInvoked, parseFrontmatter } from "./frontmatter.ts"
+import { isUserInvoked, parseFrontmatter } from "../src/frontmatter.ts"
 
 const root = path.resolve(path.dirname(fileURLToPath(import.meta.url)), "..")