hotfix(deploy): serve i18n JSON no-cache so translations refresh after deploy

[jhosepmyr]

Description

Production hotfix for stale translations across devices: the deploy synced every non-index.html asset to S3 with Cache-Control: public, max-age=31536000, immutable, including the non-fingerprinted i18n/{lang}.json files. immutable tells browsers to cache them for a year without revalidating, so once a device cached en.json/es.json it never picked up translations added in later deploys — hence integration/billing labels rendering in one browser but not another. The CloudFront /* invalidation refreshes the CDN, but a browser's immutable copy never asks the CDN again.

Exclude i18n/* from the immutable sync and upload it (like index.html) with no-cache, must-revalidate, so browsers revalidate the JSON (ETag → 304) and get the fresh file after each deploy. Pairs with the already-shipped per-load ?v= cache-bust, which unsticks devices currently holding an immutable copy on their next load after this deploys.

Feature module / area: build / ci (deploy workflow)

Related issue / US: —

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Type of Change

• fix — bug fix
• build / ci — build, dependencies, or CI/CD

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Checklist

• The PR targets develop (not main) — N/A: this is a hotfix, intentionally targeting main (a matching bugfix/* PR carries it to develop)
• Branch name follows feature/*, bugfix/*, or hotfix/*
• Commits follow Conventional Commits
• No secrets, credentials, or .env content committed
• Deploy workflow YAML validated (parses cleanly)

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How to Test

1. Merge + deploy to production.
2. On a device that currently shows stale/raw integration or billing labels, reload — the new main.js (index.html is no-cache) loads the app, which requests /i18n/{lang}.json?v=…; the browser bypasses its immutable copy and fetches the now-no-cache file → fresh translations.
3. Verify in DevTools → Network that i18n/en.json responds with Cache-Control: no-cache, must-revalidate (not immutable).

Notes

• Hotfix → main. A bugfix/i18n-immutable-cache PR applies the same change to develop.
• No app code change; the ?v= client cache-bust is already on main (shipped via the release PR).