infra: remove dead Hashnode cross-post channel (#20)

Hashnode has been failing every cross-post run for the past month
(seen on 2026-05-12 and again on 2026-05-18, both with the same
"Unexpected token '<', '<!DOCTYPE'..." symptom indicating the API now
returns HTML where it used to return JSON). The platform itself
appears to be defunct, so rather than chase a moving API surface,
this removes the integration entirely.

Removed:
- scripts/channels/hashnode.mjs (the channel module)
- scripts/__tests__/hashnode.test.mjs (5 tests, all green prior)
- Hashnode entries in the cross-post.yml and update-cross-post.yml
  workflow env blocks (HASHNODE_TOKEN, HASHNODE_PUBLICATION_ID)
- Hashnode imports + ALL_CHANNELS entries in scripts/cross-post.mjs
  and scripts/update-cross-post.mjs
- Mentions of Hashnode in usage docstrings and the update-cross-post
  channels description

Remaining cross-post surface: dev.to (post + update) and Bluesky
(post only). Both still passing the unit suite (32 tests, was 37).
Build clean, 17 pages.

The HASHNODE_TOKEN and HASHNODE_PUBLICATION_ID GitHub Secrets are
left in place since removing them via the API is out of scope for
this PR; harmless once nothing references them.

Author: ndreno

.github/workflows/cross-post.yml

@@ -36,8 +36,6 @@ jobs:
       - name: Cross-post
         env:
           DEV_TO_API_KEY: ${{ secrets.DEV_TO_API_KEY }}
-          HASHNODE_TOKEN: ${{ secrets.HASHNODE_TOKEN }}
-          HASHNODE_PUBLICATION_ID: ${{ secrets.HASHNODE_PUBLICATION_ID }}
           BSKY_HANDLE: ${{ secrets.BSKY_HANDLE }}
           BSKY_APP_PASSWORD: ${{ secrets.BSKY_APP_PASSWORD }}
         run: |

.github/workflows/update-cross-post.yml

@@ -7,7 +7,7 @@ on:
         description: 'Slug to re-push (uses current source markdown)'
         required: true
       channels:
-        description: 'Comma-separated channel filter (e.g. devto,hashnode). Empty = all updatable channels.'
+        description: 'Comma-separated channel filter (e.g. devto). Empty = all updatable channels.'
         required: false
       dry_run:
         description: 'Dry run (look up posts, do not update)'
@@ -30,8 +30,6 @@ jobs:
       - name: Update cross-posts
         env:
           DEV_TO_API_KEY: ${{ secrets.DEV_TO_API_KEY }}
-          HASHNODE_TOKEN: ${{ secrets.HASHNODE_TOKEN }}
-          HASHNODE_PUBLICATION_ID: ${{ secrets.HASHNODE_PUBLICATION_ID }}
         run: |
           ARGS="--slug=${{ github.event.inputs.slug }}"
           if [ -n "${{ github.event.inputs.channels }}" ]; then

scripts/__tests__/hashnode.test.mjs

@@ -14,10 +14,9 @@
 
 import * as bluesky from './channels/bluesky.mjs';
 import * as devto from './channels/devto.mjs';
-import * as hashnode from './channels/hashnode.mjs';
 import { detectNewlyPublished, loadArticle, resolvePosts } from './lib/post-source.mjs';
 
-const ALL_CHANNELS = [devto, hashnode, bluesky];
+const ALL_CHANNELS = [devto, bluesky];
 
 function parseArgs(argv) {
   const out = { dryRun: false, slug: null, channels: null };

scripts/channels/hashnode.mjs

@@ -1,9 +1,8 @@
 #!/usr/bin/env node
 // Re-publish the current source markdown to existing cross-posts.
 // Use this when an already-cross-posted article gets a substantive edit
-// that needs to propagate to dev.to, Hashnode, etc. The companion
-// cross-post script is intentionally skip-if-exists, so edits do not
-// flow through it.
+// that needs to propagate to dev.to. The companion cross-post script is
+// intentionally skip-if-exists, so edits do not flow through it.
 //
 // Usage:
 //   node scripts/update-cross-post.mjs --slug=foo
@@ -12,14 +11,13 @@
 //   node scripts/update-cross-post.mjs --slug=foo --channels=devto
 //
 // Channels are auto-discovered. Only channels that export an `update`
-// function are eligible (Bluesky is excluded — editing a feed item in
+// function are eligible (Bluesky is excluded - editing a feed item in
 // place is rude / unsupported).
 
 import * as devto from './channels/devto.mjs';
-import * as hashnode from './channels/hashnode.mjs';
 import { loadArticle, resolvePosts } from './lib/post-source.mjs';
 
-const ALL_CHANNELS = [devto, hashnode];
+const ALL_CHANNELS = [devto];
 
 function parseArgs(argv) {
   const out = { slugs: [], dryRun: false, channels: null };
@@ -86,7 +84,7 @@ export async function processArticle(article, channels, dryRun) {
 async function main() {
   const args = parseArgs(process.argv.slice(2));
   if (args.slugs.length === 0) {
-    console.error('Usage: node scripts/update-cross-post.mjs --slug=<slug> [--slug=<slug>...] [--channels=devto,hashnode] [--dry-run]');
+    console.error('Usage: node scripts/update-cross-post.mjs --slug=<slug> [--slug=<slug>...] [--channels=devto] [--dry-run]');
     process.exit(1);
   }