[ADD] Claude Code ecosystem adapted from Copilot config

Port .github Copilot setup to Claude Code:
- CLAUDE.md: condensed project instructions (auto-loaded each session)
- .claude/skills: per-language guides (odoo-python, odoo-xml-views,
  odoo-qweb-html, odoo-javascript) + openspec-* workflow skills
- .claude/commands/opsx: /opsx:explore|propose|apply|archive slash commands

Original .github/ files kept untouched as extended reference.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.claude/skills/odoo-javascript/SKILL.md

@@ -0,0 +1,24 @@
+---
+name: odoo-javascript
+description: JavaScript/Odoo frontend conventions for this repo (modules, tours, events, lazy loading). Use when editing JS in static/src/js/ of Odoo addons.
+metadata:
+  type: reference
+---
+
+# JavaScript (Odoo Web/Frontend)
+
+## Style and conventions
+- ES6+ (`let`/`const`, arrow functions). Linting with ESLint (`.eslintrc.js` at root).
+- Odoo pattern: AMD modules (`odoo.define`).
+- **No business logic in JS, only UI and events.** Business logic lives in Python.
+- Comments to explain hacks or workarounds.
+
+## Key patterns
+- Scripts in `static/src/js/`.
+- UI tours registered with `web_tour.tour` (test: true, url, steps).
+- **Delegated** events for dynamic elements (lazy loading, infinite scroll in `website_sale_aplicoop`).
+- AJAX via Odoo helpers (`ajax.jsonRpc`).
+
+## Common mistakes
+- Business logic in JS → move it to Python.
+- Listeners lost after DOM manipulation → reattach via event delegation.