GOAL - W4 Hreflang correctness (odoo-expertos). Branch: fix/w4-hreflang. Repo: C:\Users\eugen\.cursor\projects\Odoo Expertos\odoo-expertos. Work ONLY in this repo. Context: FULL-AUDIT-REPORT.md (Part A sec 1). Category index pages (odoo/, odoo-hosting/, odoo-ia/) have ZERO hreflang. Some pages emit hreflang="es" pointing into a /de//fr//pt//ar/ subtree (a Spanish-slug URL under a language prefix) which 404s; the es alternate and x-default must point to the ROOT Spanish URL (no language prefix). TASK: Write a codemod over all /index.html: (1) ensure each page has a hreflang block for the languages that actually exist for it, all on www, plus x-default pointing to the ROOT es URL. (2) Fix any hreflang="es" or x-default href that contains /de/ /fr/ /pt/ /ar/ /en/ so it points to the root path (strip the language segment). (3) Add the hreflang block to the 3 category index pages. CONSTRAINTS: only touch hreflang/link-alternate tags. Don't change body content. PROVE each turn: run powershell -File seo-audit-2026-05-27\REVIEW.ps1 -Only W4 and paste the full output. DONE WHEN: the output contains "W4: PASS" (category pages without hreflang=0 AND es-hreflang into a /lang/ subtree=0), AND you committed on branch fix/w4-hreflang (show git log -1 --oneline). Stop after 20 turns if blocked and report the FAIL detail.