Restore MQTT access inventory and stabilize Lighthouse

[n30nex]

What changed

• restores the public read-only MQTT account inventory for Beacon and CoreScope in English and French
• makes the inventory maintenance rule explicit while keeping usernames, passwords, and tokens out of the site
• warms Lighthouse once before measured routes so a cold Chrome startup cannot sink only the first page
• keeps the existing Lighthouse budgets unchanged and adds a regression check for the bilingual inventory

Why

The post-merge run for PR #86 failed only the first Lighthouse measurement: the English home page scored 0.73, while the next six routes scored 0.97 to 1.00. Validation passed and the full browser job passed. This fixes the cold-start measurement without weakening the quality gate.

Failed run: https://github.com/MeshCore-ca/MeshCore-Canada/actions/runs/33650486354/job/100316356666

Local verification

• npm run test:content — 73 passed
• npm run audit:lighthouse — home 1.00; other performance scores 0.96 to 1.00; all budgets passed
• npm run test:browser:chromium — 66 passed, 5 skipped
• strict bilingual build and built-link audit passed

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-02T16:01:15.988591Z	634e5d4	PR opened

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review" or "@codex security review".

Codex reacts with 👀 while any review is running, comments if it has suggestions, and reacts with 👍 once all reviews finish with no findings.