fix(dev-1696): bump sharp to 0.35.4

[spur-vuln-author]

Context

Batched group (ticket_group_key tg:sharp:pnpm-lock.yaml, 2 advisories) against sharp, all in pnpm-lock.yaml:

• GHSA-rgj7-g3m4-5g8c — sharp < 0.35.4 (high)
• GHSA-f88m-g3jw-g9cj — sharp < 0.35.0 (high)

Transitive dependency (not declared in any package.json), resolved via pnpm-lock.yaml. No Dependabot PR exists for either advisory, so this PR was constructed directly from the highest first_patched_version across the group (0.35.4).

Test evidence

No Dependabot PR existed; constructed from first_patched_version 0.35.4 (highest across the batch). Added a pnpm.overrides entry and regenerated the lockfile with pnpm install --lockfile-only. Confirmed via lockfile inspection that sharp now resolves to 0.35.5 (previously 0.34.1), satisfying >= 0.35.4 for both advisories. Companion-file scan (Dockerfiles, .nvmrc, go.mod, CI workflow YAML, etc. hardcoding 0.34.1) found no hits.

Risk

Low. Lockfile-only transitive dependency bump, resolves both batched advisories at once. Group max severity high; Tier 1 / 90-day SLA.

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[spur-vuln-reviewer]

Escalating: Gate 3 (diff equivalence) mechanically FAILed. gate3-check.sh: GATE3 FAIL target=sharp manifest=pnpm-lock.yaml pr_version=? required=0.35.4 alerts=87,119 extra_files=1 state=open. Detail: the helper has no extraction rule for ecosystem=npm manifest basename=pnpm-lock.yaml, so it could not extract the new sharp version from the diff, and flagged package.json as a file outside {manifest, lockfile} (which is actually the expected direct-dependency file for an npm/pnpm version bump). This looks like a tooling gap in gate3-check.sh (no pnpm-lock.yaml parser) rather than a real diff deviation, but per the review contract a mechanical Gate 3 FAIL is never re-derived or second-guessed by the reviewer. Required version per max open Dependabot alert(s) 87,119: 0.35.4. Not merged. A human must review this. This reviewer will not act on this PR again. [[spur-vuln-reviewer: escalated diff-mismatch-constructed]]