fix(contracts): fix MDX rendering for contract addresses composable pages

[Copilot]

The contract addresses page failed to render across all three tabs (About, Gateway, Orchestrator) due to a duplicate contractAddresses import in a nested MDX composable chain. Mintlify merges parent/child composable scope — re-importing the same identifier in the child caused a scope collision that crashed the render pipeline.

Root Cause

livepeer-contract-addresses.mdx          ← imports { contractAddresses }
  └─ verify-contract-addresses.mdx       ← also imports { contractAddresses } ❌ collision

contractAddresses is only used as a prop value in the child (<ContractVerifier data={contractAddresses} />), so it resolves correctly from parent scope without re-import.

Changes

• verify-contract-addresses.mdx — removed duplicate import { contractAddresses } (root cause); added missing frontmatter (repo standard)
• livepeer-contract-addresses.mdx — fixed <Danger> block: replaced <br/><br/> with blank lines so MDX re-enters markdown mode and list items render as <ul> rather than literal text; corrected stale mixed-case anchor #No-Trust-On-chain-Address-Verification → #no-trust-on-chain-address-verification
• v2/gateways/.../contract-addresses.mdx — corrected 'Twitter:card' → 'twitter:card' in frontmatter

Scope

• snippets/composables/pages/canonical/livepeer-contract-addresses.mdx
• snippets/composables/pages/canonical/verify-contract-addresses.mdx
• v2/gateways/resources/reference/technical/contract-addresses.mdx

Validation

node operations/tests/unit/mdx.test.js
# ✅ MDX validation passed (532 files checked) — no regressions

Follow-up Tasks

None.

Type of Change

• Bug fix (fixes an issue)
• New content (adds new documentation)
• Content update (improves existing content)
• Style/formatting fix
• Information architecture change
• Other (please describe)

Related Issues

Changes Made

• Removed duplicate contractAddresses import from nested MDX child composable
• Fixed <Danger> block markup — proper blank-line separation for markdown list rendering
• Corrected mixed-case anchor fragment to lowercase (#no-trust-on-chain-address-verification)
• Corrected 'Twitter:card' meta key casing in gateway page frontmatter
• Added frontmatter to verify-contract-addresses.mdx

Testing

• Tested locally with npm run dev
• Verified all links work
• Checked formatting and style
• Reviewed against style guides
• Screenshots (if UI changes)

Screenshots (if applicable)

N/A

Checklist

• My changes follow the style guides
• I've reviewed the Component Library for available components
• I've updated related pages if needed
• I've checked for broken links
• My changes are clear and easy to understand
• I've tested locally
• I've added/updated keywords and metadata if needed

Additional Notes

All three parent pages (v2/about/..., v2/gateways/..., v2/orchestrators/...) import the same composable, so fixing the composable and its child resolves the rendering failure across all three tabs simultaneously.

Governance Approval

Not required for this PR.

Copy Governance Gate - L5

Auto-checked by CI (lint-copy.js + lint-structure.js)

• No Tier 1 banned words or phrases
• No unresolved {/* REVIEW: */} flags in rendered content
• No non-USD currency outside declared regional scope
• No empty cells in decision tables
• pageType, audience, lastVerified present in frontmatter

Human review required

Sequence (L2)

• Page opens with operator outcome - value kept, no conditionals
• Majority operator path is featured before variants
• Introduced paths are developed on-page or linked

Completeness (L3)

• Decision aids (tables, matrices, flowcharts) are complete - no placeholders
• Every warning or consequence is followed by a prevention action and link
• Primary actions and URLs appear in body copy (not only in accordions)

Tone (L4)

• No sentence ends on a hedge, disclaimer, or restatement
• No section ends with a Note that apologises rather than forward-points

Brief compliance

• L0 (Q1-Q4) was completed before drafting
• L1 persona mapping table was completed before drafting