docs: align en/ structure with main README

- Simplify language badges (zh, en, more languages)
- Add X badge @123olp
- Reorganize prompts: 00-meta, 01-system, 02-coding, 03-user
- Reorganize skills: 00-meta, 01-ai-tools, 02-databases, 03-crypto, 04-dev-tools
- Update all path references

i18n/en/skills/02-databases/postgresql/references/index.md

@@ -0,0 +1,12 @@
+TRANSLATED CONTENT:
+# Postgresql Documentation Index
+
+## Categories
+
+### Getting Started
+**File:** `getting_started.md`
+**Pages:** 36
+
+### Sql
+**File:** `sql.md`
+**Pages:** 460