fix(docs): pull bb.js runtime deps via portal in examples

[charlielye]

Problem

ci/docs/examples/bootstrap.sh execute is failing repo-wide (every fresh install since 2026-06-26) with:

@aztec/bb.js/src/barretenberg_wasm/fetch_code/node/index.ts:4
import pako from 'pako';
SyntaxError: The requested module 'pako' does not provide an export named 'default'

Root cause

The recursive_verification example links @aztec/bb.js via yarn's link: protocol, which symlinks the package but does not install its own dependencies. To compensate, the example's config.yaml hand-listed bb.js's runtime deps (pako, msgpackr, comlink, idb-keyval, commander, tslib) — but unversioned (npm:pako). The bootstrap turns those into yarn add pako = latest.

pako@3.0.0 (published 2026-06-26) dropped the CommonJS/ESM default export (its ESM entry moved to named-exports-only), so bb.js's import pako from 'pako' throws under the runner's tsx/esm + --preserve-symlinks. Pre-06-26 the same bare install resolved 2.2.0 and worked; that's why older next runs were green.

Fix

Add portal: support to the examples dependency parser (lib.sh/bootstrap.sh) and pull bb.js via portal: instead of link: + a hand-mirrored dep list. portal: installs the package's declared dependencies at the versions it pins, so:

• pako resolves to 2.2.0 (bb.js pins ^2.1.0), not 3.0.0.
• The manual npm: list is deleted — bb.js's own package.json is the single source of truth, so this drift/float class of regression can't recur.

link: (which intentionally does not install deps) remains for the noir packages.

Verification

• Reproduced locally on the CI Node (v24.12.0): import pako from 'pako' works on 2.1.0/2.2.0, throws the exact CI error on 3.0.0.
• Verified yarn add @aztec/bb.js@portal:<path> installs bb.js's transitive deps at its pinned ranges (pako 2.2.0, msgpackr 1.12.1, comlink 4.4.2); yarn itself notes portal + --preserve-symlinks is the intended pairing (which the runner already uses).
• Verified the parser emits @aztec/bb.js@portal:<repo>/barretenberg/ts/bb.js with no manual npm deps and no warnings; bash -n clean.
• Not run locally: the full docs/examples execute pipeline (needs the built monorepo + a live network) — relying on CI for the end-to-end confirmation.