docs: fix AI-First heading visibility and index navigation

- Remove leading blank line and --- separator before H1 in
  03-ai-integration.md (EN + BG) to prevent markdown rendering issues
- Fix broken language switcher links in en/index.md and bg/index.md
- Add documentation TOC tables to both index files for proper navigation

docs/en/03-ai-integration.md

@@ -1,8 +1,5 @@
-
 [← Back to Index](index.md)
 
----
-
 # AI-First Design Philosophy
 
 ## Why AI-First?

docs/en/index.md

@@ -7,7 +7,7 @@
 
 | 🇬🇧 English | 🇧🇬 Български |
 |------------|-------------|
-| [English Documentation](en/index.md) | [Българска Документация](bg/index.md) |
+| [English Documentation](index.md) | [Българска Документация](../bg/index.md) |
 
 ## Quick Links
 
@@ -17,6 +17,18 @@
 - **AI Integration:** DeepSeek API, OpenAI-compatible, Xiaomi MiMo
 - **Test Suite:** [Clojure Test Suite Compatibility](07-clojure-test-suite.md) — cross-dialect compliance testing
 
+## Documentation
+
+| # | Topic | File |
+|---|-------|------|
+| 1 | Getting Started | [01-getting-started.md](01-getting-started.md) |
+| 2 | Architecture | [02-architecture.md](02-architecture.md) |
+| 3 | AI Integration | [03-ai-integration.md](03-ai-integration.md) |
+| 4 | API Reference | [04-api-reference.md](04-api-reference.md) |
+| 5 | User Guide | [05-user-guide.md](05-user-guide.md) |
+| 6 | Roadmap | [06-roadmap.md](06-roadmap.md) |
+| 7 | Clojure Test Suite | [07-clojure-test-suite.md](07-clojure-test-suite.md) |
+
 ## Why Bara Lang?
 
 Unlike every other Clojure dialect, Bara Lang has **zero dependency on the Java ecosystem** — no JVM, no GraalVM, no Google Closure Compiler, no Java standard library.