feat: create rust-analyzer project selector

Substrate development is HEAVY. Our simple chain has over 2000
dependencies in total, most of which are unused and just included
because of the umbrella dependency `polkadot-sdk`.

This new crate allows you to select which crates and dependencies
you want rust-analyzer to index:

```sh
just select
just select pallet-torus0,pallet-emission0
just select node 1 # will only fetch up to second-level transient dependencies
```

Author: saiintbrisson

.gitignore

@@ -19,3 +19,5 @@
 
 # Git Hooks
 .pre-commit-config.yaml
+
+rust-project.json

.vscode/settings.json

@@ -8,7 +8,12 @@
   "rust-analyzer.check.extraEnv": {
     "SKIP_WASM_BUILD": "1"
   },
-  "rust-analyzer.cargo.features": ["runtime-benchmarks", "testnet"],
+  // "rust-analyzer.cargo.features": ["runtime-benchmarks", "testnet"],
+  "rust-analyzer.check.overrideCommand": [
+    "cargo",
+    "check",
+    "--message-format=json"
+  ],
   "coverage-gutters.coverageFileNames": ["target/cov.xml"],
   // Spell checker
   "cSpell.words": [