docs: fix duplicate changelog sections and restore unreleased entry from pr/72

Author: bug-ops

CHANGELOG.md

@@ -6,21 +6,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
-### Changed
-
-- **C/C++ file pattern language detection** - When `lsp_servers[].file_patterns` include simple extensions such as `**/*.c` or `**/*.h`, mcpls now derives extension-to-language mappings from those patterns and overlays them onto the workspace extension map. This changes the default behavior for matching C/C++ files to prefer the configured LSP server language instead of falling back to built-in mappings or `plaintext`.
-
-## [0.3.6] - 2026-04-21
-
-### Changed
-
-- Bump rmcp from 1.3.0 to 1.4.0; remove now-redundant `tool_router` struct field (auto-generated by macro since 1.4.0)
-- Bump tokio from 1.50.0 to 1.52.0
-- Bump toml from 1.1.1 to 1.1.2
 
 ### Fixed
 
-- CI: nightly rustfmt failures when `rustfmt` component is temporarily unavailable for the latest nightly build (`--allow-downgrade`)
+- **C/C++ file pattern language detection** — `lsp_servers[].file_patterns` now derives extension-to-language mappings (e.g. `**/*.c` → `c`, `**/*.h` → `c`) and overlays them onto the workspace extension map, so configured language IDs take precedence over built-in defaults
 
 ## [0.3.6] - 2026-04-21