LS: Proc macro server connection (#6637)

crates/cairo-lang-language-server/Cargo.toml

@@ -26,6 +26,7 @@ cairo-lang-syntax = { path = "../cairo-lang-syntax", version = "~2.8.5" }
 cairo-lang-test-plugin = { path = "../cairo-lang-test-plugin", version = "~2.8.5" }
 cairo-lang-utils = { path = "../cairo-lang-utils", version = "~2.8.5" }
 crossbeam = "0.8.4"
+governor = { version = "0.7.0", default-features = false, features = ["std", "quanta"]}
 indent.workspace = true
 indoc.workspace = true
 itertools.workspace = true
@@ -35,6 +36,7 @@ lsp-types = "=0.95.0"
 rustc-hash = "1.1.0"
 salsa.workspace = true
 scarb-metadata = "1.13"
+scarb-proc-macro-server-types = "0.1"
 serde = { workspace = true, default-features = true }
 serde_json.workspace = true
 smol_str.workspace = true

crates/cairo-lang-language-server/src/lang/db/mod.rs

@@ -19,6 +19,7 @@ use cairo_lang_utils::Upcast;
 pub use self::semantic::*;
 pub use self::swapper::*;
 pub use self::syntax::*;
+use super::proc_macros::db::{ProcMacroDatabase, init_proc_macro_group};
 use crate::Tricks;
 
 mod semantic;
@@ -33,7 +34,8 @@ mod syntax;
     ParserDatabase,
     SemanticDatabase,
     SyntaxDatabase,
-    DocDatabase
+    DocDatabase,
+    ProcMacroDatabase
 )]
 pub struct AnalysisDatabase {
     storage: salsa::Storage<Self>,
@@ -46,6 +48,9 @@ impl AnalysisDatabase {
 
         init_files_group(&mut db);
         init_lowering_group(&mut db, InliningStrategy::Default);
+        // proc-macro-server can be restarted many times but we want to keep these data across
+        // multiple server starts, so init it once per database, not per server.
+        init_proc_macro_group(&mut db);
 
         db.set_cfg_set(Self::initial_cfg_set().into());
 

crates/cairo-lang-language-server/src/lang/mod.rs

@@ -2,3 +2,4 @@ pub mod db;
 pub mod diagnostics;
 pub mod inspect;
 pub mod lsp;
+pub mod proc_macros;