chore(deps): bump undici from 6.27.0 to 6.28.0 in /web/backend

[dependabot]

Bumps undici from 6.27.0 to 6.28.0.

Release notes

Sourced from undici's releases.

v6.28.0

⚠️ Security fixes

• GHSA-m8rv-5g2x-5cg5: a malicious type property on a duck-typed blob-like HTTP/1.1 request body could inject CRLF sequences into the generated content-type header. Undici now coerces and validates the value before adding it to the request. Fixed by 740a0b7c.
• GHSA-8xcm-r25x-g524: the retry interceptor could expose a stale Content-Length after resuming a partial response, potentially causing downstream response desynchronization, hangs, or corruption. Undici now rejects partial responses whose Content-Length is inconsistent with Content-Range. Fixed by cba3a52a, with corrected fixtures in 4fd5a0c6.
• GHSA-v3r7-h72x-cjcm: unsanitized domain and unparsed values passed to setCookie() could inject cookie attributes. Undici now validates cookie domains, paths, and unparsed attributes more strictly. Fixed by af748404.

GHSA-4cwx-7wf7-3272 and GHSA-jr45-8vmc-qm54 affect the cache interceptor in Undici v7 and v8; Undici v6 is not in their affected version ranges.

Full Changelog: nodejs/undici@v6.27.0...v6.28.0

Commits

• 01a912e Bumped v6.28.0 (#5591)
• 481ecfc Use Node 22 and npm 11 to release
• 740a0b7 fix: validate blob body content type
• 2698e49 fix: validate coerced header values for CRLF (#5579)
• 4fd5a0c test(retry): correct broken content-range fixtures in retry-handler.js
• cba3a52 fix(retry): reject partial content length mismatch
• af74840 fix: harden cookie domain, path, and unparsed attribute validation
• See full diff in compare view

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[padak]

Verified as part of a batch review of all six open Dependabot PRs (#554, #555, #558, #559, #563, #564), all of which close open Dependabot security alerts.

All six were merged into a single throwaway branch off main and validated together, because a clean line-based merge of a lockfile does not by itself guarantee the lockfile stays internally consistent:

• all six merge into main with no conflict;
• web/frontend: npm ci succeeds and npm run build (tsc -b && vite build) passes — tsc type-checks the mermaid.render() / mermaid.initialize() call sites against mermaid 11.16.1's own type definitions, which is the only safety net here since the SPA has no tests;
• npm ls dompurify confirms the overrides block still pins dompurify 3.4.13 tree-wide, including under mermaid (which itself declares ^3.3.3);
• web/backend: npm ci succeeds;
• Python: full suite green on the combined state with cryptography 50.0.0 — 5489 passed, 161 skipped;
• cryptography 50.0.0's breaking changes (FFDH deprecation, stricter DER/X.509/OCSP parsing, PKCS#7 decryption) do not touch kbagent's usage, which is limited to RSA keypair generation plus PKCS8/SPKI PEM serialization in services/workspace_service.py. Smoke-tested that exact API surface against 50.0.0.

Note for follow-up, unrelated to these PRs: npm audit reports a high-severity advisory for nanoid@3.3.16 (GHSA-2v37-7h3g-55p8) in both web/frontend and web/backend, pulled in transitively via postcss. It is build-time only and never reaches the shipped bundle, and Dependabot has not raised an alert for it.