chore: rebrand Clojure/Nim → Bara Lang across codebase

- Bulk replace Clojure/Nim → Bara Lang in src/, lib/, examples/, benchmarks/,
  experiments/, books/, LICENSE, cljnim.nimble, PLAN.md, AI_AGENT.md
- Rename book chapters: 05-clojure-nim.md → 05-bara-lang.md (en + bg)
- Update all chapter index links and anchors
- Replace project-specific 'Clojure' references with 'Bara Lang' in
  experiments/, src/ai_assist.nim, src/tui_screens.nim, src/emitter.nim,
  src/reader.nim, src/types.nim, lib/cljnim_runtime*.nim
- Keep legitimate JVM Clojure/ClojureScript/Clojure CLR references intact

books/clojure-book/bg/index.md

@@ -8,11 +8,11 @@
 - **Анонимни функции** - [5.2](bg/01-fundamentals.md#52-анонимни-функции)
 - **Аритности** - [5.1.2](bg/01-fundamentals.md#512-множество-арности)
 - **Асинхронно програмиране** - [16](bg/01-fundamentals.md#16-coreasync), [4](bg/04-recipes.md#4-async-рецепти)
-- **Атом (Atom)** - [11.1](bg/01-fundamentals.md#11-атоми-atoms), [5](bg/05-clojure-nim.md#конкурентност)
-- **AI интеграция** - [5](bg/05-clojure-nim.md#ai-асистирана-разработка)
-- **AI агенти** - [5](bg/05-clojure-nim.md#json-repl-за-ai-агенти)
-- **Clojure/Nim** - [5](bg/05-clojure-nim.md) — Нативна компилация, AI, JSON REPL
-- **Cross-compilation** - [5](bg/05-clojure-nim.md#cross-compilation-target-и) — JS, WASM, shared libraries
+- **Атом (Atom)** - [11.1](bg/01-fundamentals.md#11-атоми-atoms), [5](bg/05-bara-lang.md#конкурентност)
+- **AI интеграция** - [5](bg/05-bara-lang.md#ai-асистирана-разработка)
+- **AI агенти** - [5](bg/05-bara-lang.md#json-repl-за-ai-агенти)
+- **Bara Lang** - [5](bg/05-bara-lang.md) — Нативна компилация, AI, JSON REPL
+- **Cross-compilation** - [5](bg/05-bara-lang.md#cross-compilation-target-и) — JS, WASM, shared libraries
 
 ## Б