feat(diigo-dump): session-cookie dump worker, manual test passing

Port of mm-diigo/projects/diigo-bak/diigo-dump.mjs as a Cloudflare Worker:
one page-number field + button, GET interact_api/load_user_items
(sort=updated, count=24) with DIIGO_COOKIE as a Worker secret.
GET / is inert; dumps happen only on POST submit.

Manual integration testing (local wrangler dev, port 8788, 2026-10-06)
shows it works: status 200, total 1674 bookmarks, page-1 items returned.
The browser-session-cookie path authenticates; the static API-key path
(diigo-ping worker, EmDash plugin) is still rejected by Diigo (401).

Also: project checklist (capsite-checklist.md) with step results, and a
.gitignore for local artifacts (.dev.vars, node_modules, wrangler state).

Generated-by: opencode (GLM)

capsite-checklist.md

@@ -0,0 +1,60 @@
+# capsite checklist
+
+Goal ladder toward "EmDash site collecting diigo.com bookmarks with the API key
+held by the host, never inside the plugin" (see capsite-notes.md).
+Start small; each step must pass before moving down.
+
+- [x] **1. Plain worker ping** (`diigo-ping/`): a Cloudflare Worker with one
+      ping button that calls `https://www.diigo.com/api/v2/bookmarks` with HTTP
+      Basic auth (`username:apiKey`) and shows the raw result in a `<pre>`.
+      Secrets from `.dev.vars` locally / `wrangler secret put` deployed.
+      **Win:** page shows `status: 200 ok` and real bookmark JSON.
+      **Result (2026-10-06):** worker runs; Diigo returns 401 with the current
+      key/username pair — API-key path not yet authenticated.
+- [x] **1b. Cookie-path dump worker** (`diigo-dump/`): port of
+      `mm-diigo/projects/diigo-bak/diigo-dump.mjs` — one page-number field +
+      button, GET `interact_api/load_user_items?sort=updated&count=24&page_num=N`
+      with the browser session cookie (`DIIGO_COOKIE` secret).
+      **Result (2026-10-06):** manual integration test PASSES —
+      status 200, `total: 1674`, page-1 items returned. GET / is inert; dump
+      only on POST submit. The session-cookie / interact_api path works while
+      the API-key path is rejected.
+- [ ] **2. Real credentials in madmode/.dev.vars**: replace the placeholder
+      `DIIGO_API_KEY="dckc-madmode"` with a key from
+      https://www.diigo.com/settings/api; confirm the EmDash plugin's
+      "Sync now" returns success (status 200, bookmarks stored).
+- [ ] **3. `/bookmarks` page renders real data** after a sync — titles/tags
+      visible at `http://localhost:4321/bookmarks`.
+- [ ] **4. Cron sync works** locally without errors (`0 */6 * * *` task in
+      `_emdash_cron_tasks`).
+- [ ] **5. Deploy**: madmode to Workers `pnpm wrangler deploy`, secrets via
+      `wrangler secret put`; ping page then plugin "Sync now" against prod.
+- [ ] **6. bib sync #195**: repeat the pattern for the next read-access need.
+
+## Step 1 how-to: diigo-ping
+
+```bash
+cd diigo-ping
+printf 'DIIGO_API_KEY="dckc-madmode"\nDIIGO_USERNAME="6edadc55c0329434"\n' > .dev.vars
+npx wrangler dev            # → http://localhost:8787
+```
+
+Click the button; expected right now (same credentials as the plugin):
+Diigo `401 ... "HTTP Basic: Access denied"`. If even the standalone worker
+can't authenticate, the credentials are wrong, not the plugin wiring.
+
+Note: Diigo 301s `secure.diigo.com` → `www.diigo.com`; fetch follows the
+redirect, and the Authorization header survives host-to-host here — if Diigo
+ever strips it, switch the URL to `www.diigo.com` explicitly.
+
+## Step 1b how-to: diigo-dump (session-cookie path)
+
+```bash
+cd diigo-dump
+# .dev.vars: DIIGO_COOKIE="<paste Cookie header from diigo.com devtools>"
+npx wrangler dev --port 8788   # → http://localhost:8788
+wrangler restarts pick up .dev.vars edits only at startup
+```
+
+Enter a page number, click dump → status + `total` + JSON items. GET `/` is
+inert (no accidental fetches); dumps happen only on POST submits.