fix(linkedin): close dogfood friction (S14)

Close all 9 friction points from the S13 newsletter dogfood (operator
elected to fix F6-F9 rather than defer):

- F1: namespace all subagent_type calls in newsletter.md to
  linkedin-thought-leadership:<name> (4 sites + canonical note)
- F2: document agent invocation form + reload requirement in CLAUDE.md
  + README.md (reload itself is an operator action)
- F3: add edition-config / edition-delingstekst / edition-HANDOVER
  templates under config/ + wire into Steps 0 and 8 + footer
- F4: reconcile draft path to <serie>/NN-utkast.md (series root)
- F5: de-hardcode series root (explicit arg / LTL_SERIES_ROOT / default)
- F6: config-derive carousel editions (remove Seres CAROUSEL set);
  correct samle comment
- F7: build-html.mjs exits non-zero when zero HTML produced
- F8: guard parseDelingstekst (graceful ENOENT) + correct Step 8 wording
- F9: relocate agents/README.md -> docs/agents-capability-matrix.md

Re-tested: 87/87 plugin tests pass; build-html/build-linkedin behavior
re-verified live. Per-item outcomes logged in dogfood-S13-friction.md.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

plugins/linkedin-thought-leadership/render/build-html.mjs

@@ -1030,16 +1030,20 @@ ${CLIENT_JS}
 // ---------------------------------------------------------------------------
 // Main
 // ---------------------------------------------------------------------------
+// Returnerer antall HTML-filer skrevet. Eksitkoden settes av CLI-guarden under
+// (S14/F7): main() kaller aldri process.exit() selv, slik at modulen kan
+// importeres/testes uten å drepe prosessen.
 export function main() {
   const args = process.argv.slice(2);
   if (!args.length) {
     console.error("Bruk: node build-html.mjs <fil.md> [flere.md ...]");
-    process.exit(1);
+    return 0;
   }
   // Output følger serien (kjøres fra serie-mappa), ikke scriptet i tools/.
   const outDir = path.join(process.cwd(), "review");
   if (!fs.existsSync(outDir)) fs.mkdirSync(outDir, { recursive: true });
 
+  let written = 0;
   for (const arg of args) {
     const inPath = path.isAbsolute(arg) ? arg : path.join(process.cwd(), arg);
     if (!fs.existsSync(inPath)) {
@@ -1054,11 +1058,20 @@ export function main() {
     const outPath = path.join(outDir, base + ".html");
     fs.writeFileSync(outPath, html, "utf8");
     console.log(`Skrev ${outPath} (${(html.length / 1024).toFixed(1)} KB)`);
+    written++;
   }
+
+  // S14/F7: en typo'd/manglende input-fil ga tidligere exit 0 uten HTML (stille
+  // footgun). Skrev vi ingenting, er det en feil — rapporter og la CLI-guarden
+  // sette ikke-null exit.
+  if (written === 0) {
+    console.error(`Ingen HTML produsert (0 av ${args.length} input-fil(er) funnet) — sjekk filnavn og sti.`);
+  }
+  return written;
 }
 
 // CLI-guard: kjør kun når scriptet startes direkte, ikke ved import
-// (mønster fra hooks/scripts/state-updater.mjs).
+// (mønster fra hooks/scripts/state-updater.mjs). Exit non-zero hvis ingen HTML.
 if (import.meta.url === `file://${process.argv[1]}`) {
-  main();
+  process.exit(main() > 0 ? 0 : 1);
 }