fix: repair .zip download and serve raw SKILL.md without attribution comment (#241)

* fix: generate SKILL.zip for every skill, not just multi-file ones

The skill detail page shows an unconditional 'Download .zip' link for
every skill (introduced in #169), but the zip endpoint only generated a
file for multi-file skills. Single-file skills therefore linked to a
zip that was never built, returning 404.

Drop the multi-file guard so a zip is generated for every skill:
single-file skills get a zip containing just SKILL.md; multi-file skills
continue to bundle SKILL.md plus their references/ tree.

* fix: stop prepending attribution comment to raw SKILL.md

The /skills/<name>/SKILL.md endpoint prepended an HTML comment with
source/origin/publisher/license/updated metadata (added in #171). This
made the served markdown non-identical to the repo file and cluttered
the top of the document.

Serve the raw SKILL.md bytes unchanged. Provenance is still carried in
the X-Content-Source and X-License response headers, so nothing is lost
for machine consumers.

Author: marc0olo

src/pages/.well-known/skills/[name]/SKILL.zip.ts

@@ -1,5 +1,7 @@
 // Serves /.well-known/skills/<name>/SKILL.zip at build time
-// Only generated for multi-file skills (SKILL.md + references)
+// Generated for every skill so the download link always resolves. Single-file
+// skills produce a zip containing just SKILL.md; multi-file skills bundle
+// SKILL.md plus their references/ tree.
 import type { APIRoute } from 'astro';
 import archiver from 'archiver';
 import { readdirSync, readFileSync, statSync } from 'fs';
@@ -58,7 +60,7 @@ async function buildZip(skillDir: string): Promise<Buffer> {
 
 let _cache: SkillZipData[] | null = null;
 
-async function loadMultiFileSkillZips(): Promise<SkillZipData[]> {
+async function loadSkillZips(): Promise<SkillZipData[]> {
   if (_cache) return _cache;
 
   const dirs = readdirSync(SKILLS_DIR)
@@ -76,9 +78,6 @@ async function loadMultiFileSkillZips(): Promise<SkillZipData[]> {
 
   for (const dir of dirs) {
     const skillDir = join(SKILLS_DIR, dir);
-    const files = collectFilePaths(skillDir, skillDir);
-    if (files.length <= 1) continue; // skip single-file skills
-
     const content = readFileSync(join(skillDir, 'SKILL.md'), 'utf-8');
     const name = parseName(content);
     if (!name) continue;
@@ -92,7 +91,7 @@ async function loadMultiFileSkillZips(): Promise<SkillZipData[]> {
 }
 
 export async function getStaticPaths() {
-  const skills = await loadMultiFileSkillZips();
+  const skills = await loadSkillZips();
   return skills.map((s) => ({
     params: { name: s.name },
     props: { zipBuffer: s.zipBuffer },

src/pages/skills/[slug]/SKILL.md.ts

@@ -1,11 +1,11 @@
 // Raw markdown endpoint: /skills/{slug}/SKILL.md returns the unmodified SKILL.md
-// bytes (frontmatter + body). Served with text/markdown so LLM crawlers can
-// parse it natively. An attribution header line is prepended as a markdown
-// comment so the origin stays visible even if the file is copy-pasted.
+// bytes (frontmatter + body), byte-identical to the repo file. Served with
+// text/markdown so LLM crawlers can parse it natively. Provenance is carried in
+// the X-Content-Source and X-License response headers, not in the body.
 
 import type { APIRoute } from 'astro';
 import { getAllSkills, getSkillGitInfo, getSkillRawMarkdown, githubCommitUrl } from '../../../lib/skills';
-import { SITE, absUrl } from '../../../lib/site';
+import { SITE } from '../../../lib/site';
 
 export async function getStaticPaths() {
   const skills = await getAllSkills();
@@ -19,13 +19,10 @@ export const GET: APIRoute = async ({ props }) => {
   if (!skill) return new Response('Not found', { status: 404 });
 
   const body = await getSkillRawMarkdown(skill);
-  const { sha, updatedAt } = await getSkillGitInfo(skill);
+  const { sha } = await getSkillGitInfo(skill);
   const sourceUrl = githubCommitUrl(slug, sha);
-  const attribution =
-    `<!-- source: ${absUrl(`/skills/${slug}/`)} | origin: ${sourceUrl} | ` +
-    `publisher: ${SITE.author.name} | license: ${SITE.license.spdx} | updated: ${updatedAt} -->\n`;
 
-  return new Response(attribution + body, {
+  return new Response(body, {
     headers: {
       'Content-Type': 'text/markdown; charset=utf-8',
       'X-Content-Source': sourceUrl,