refactor: remove unused grapha-rust crate and make grapha-engine publishable

grapha-rust was a dead workspace member: no crate depended on it and no
code imported it (the live Rust extractor is inlined in grapha-engine).
Remove it entirely and restore the publish chain that the engine-extraction
refactor had broken.

- Delete grapha-rust/ and drop it from workspace members
- Remove `publish = false` and the unused grapha-rust dep from grapha-engine
- Refresh README / CN README workspace structure and a stale manifest.rs comment

nous, the only external consumer, depends on grapha-core + grapha-engine via
a pinned git rev and never used grapha-rust, so it is unaffected.

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

Author: ahavili

Cargo.lock

@@ -1,3 +1,3 @@
 [workspace]
-members = ["grapha-core", "grapha-rust", "grapha-swift", "grapha-engine", "grapha"]
+members = ["grapha-core", "grapha-swift", "grapha-engine", "grapha"]
 resolver = "3"

Cargo.toml

@@ -342,9 +342,9 @@ Global developer defaults can live in `$GRAPHA_CONFIG`, `$XDG_CONFIG_HOME/grapha
 
 ```text
 grapha-core/     Shared graph, extraction, semantic, selector, and plugin types
-grapha-rust/     Rust plugin and tree-sitter extractor package
 grapha-swift/    Swift extraction: index store -> SwiftSyntax -> tree-sitter
-grapha/          CLI binary, query engines, persistence, MCP server, and web UI
+grapha-engine/   Library engine: extraction, query engines, persistence, and language plugins
+grapha/          CLI binary, MCP server, and web UI
 nodus/           Agent tooling package with skills, rules, and commands
 ```
 

README.md

@@ -271,9 +271,9 @@ operation = "set"
 
 ```text
 grapha-core/     共享图、提取、语义、选择器和插件类型
-grapha-rust/     Rust 插件和 tree-sitter 提取器包
 grapha-swift/    Swift 提取：Index Store -> SwiftSyntax -> tree-sitter
-grapha/          CLI、查询引擎、持久化、MCP 服务器和 Web UI
+grapha-engine/   库引擎：提取、查询引擎、持久化和语言插件
+grapha/          CLI、MCP 服务器和 Web UI
 nodus/           智能体工具包，包含 skills、rules 和 commands
 ```
 

docs/README.CN.md

@@ -2,7 +2,6 @@
 name = "grapha-engine"
 version = "0.4.2"
 edition = "2024"
-publish = false
 description = "Library engine for Grapha code intelligence"
 license = "MIT"
 repository = "https://github.com/oops-rs/grapha"
@@ -13,7 +12,6 @@ categories = ["development-tools"]
 
 [dependencies]
 grapha-core = { version = "0.4.2", path = "../grapha-core" }
-grapha-rust = { version = "0.4.2", path = "../grapha-rust" }
 grapha-swift = { version = "0.4.2", path = "../grapha-swift", optional = true }
 anyhow = "1"
 bincode = { version = "2", features = ["serde"] }

grapha-engine/Cargo.toml

@@ -157,7 +157,7 @@ impl Op {
 /// The per-language quality tier grapha provides.
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum LanguageTier {
-    /// Deep, language-aware extraction (Rust via grapha-rust, Swift via
+    /// Deep, language-aware extraction (Rust via tree-sitter, Swift via
     /// libIndexStore + SwiftSyntax): full graph ops.
     Deep,
     /// Tree-sitter-only structural extraction: symbol/context/usages are