Serve the whitepaper from one place, and stop cloning what cannot be cloned

Three changes, all pointing the same way: one published document, fed from one source.

`web/public/Whitepaper.pdf` was a second copy of a document that also lives on
pezkuwichain.io, in the landing tree, on three servers and in the repository the
document describes. The copies had diverged; the one bundled here was built in June and
still named a licence the project does not use and a pallet the tree does not contain.
A copy in a bundle is the hardest kind to keep current, because nothing fails when it
goes stale. It is removed, and the documentation card now links to the canonical URL, so
this application shows whatever is published rather than whatever was bundled. The
deployed hosts redirect `/Whitepaper.pdf` to the same place, so existing links keep
working.

The web build also began by cloning `pezkuwi-sdk`, first from the self-hosted GitLab and
then from GitHub. Neither is reachable: the GitLab path answers 500 to both the browser
and `git ls-remote`, and the GitHub repository is disabled. Nothing here changed -- the
workflow had not run since the second of August and the sources rotted underneath it.
The clone fed `generate-docs-structure.cjs`, which already treats the SDK as optional
and completes without it, and whose output is not served: the in-app documentation route
redirects to docs.pezkuwichain.io, which is why `.gitignore` leaves those artifacts
untracked. Swapping in another URL would not have helped either, since the run is
unauthenticated and the surviving repository is private. The step is removed.

Finally, `npm audit` reported five advisories against production dependencies, one high.
None arrived with this branch; a month of them surfaced at once on the first run.
`npm audit fix` without `--force` clears the high one and leaves two moderate, below what
the gate measures, and moves only `package-lock.json` -- no declared range changes.
`--force` was not used: it has broken this workspace's Solana dependencies before.

Verified: full pipeline green -- Web App, Backend Indexer, Migration test, Security
Audit, CodeQL and the deploy-gate wiring check.

.github/workflows/quality-gate.yml

@@ -39,11 +39,6 @@ jobs:
       - name: Checkout code
         uses: actions/checkout@v4
 
-      - name: Checkout Pezkuwi-SDK (for docs generation)
-        run: |
-          git clone https://git.pezkuwichain.io/pezkuwichain/pezkuwi-sdk.git Pezkuwi-SDK || \
-          git clone https://github.com/pezkuwichain/pezkuwi-sdk.git Pezkuwi-SDK
-
       - name: Setup Node.js
         uses: actions/setup-node@v4
         with: