fix: use Rust 1.90.0 for VectorChord simd crate compatibility

VectorChord's simd crate uses AVX-512 intrinsics that require Rust
1.90.0+ for stabilized target feature safety. Keep pgrx 0.16.1 but
upgrade the Rust toolchain. Add 1.90.0 mapping to versions.json.

Author: h0lybyte

nix/cargo-pgrx/versions.json

@@ -113,6 +113,9 @@
     "rust": {
       "1.88.0": {
         "cargoHash": "sha256-95DHq5GLnAqb3bbKwwaeBeKEmkfRh81ZTRaJ7L59DAg="
+      },
+      "1.90.0": {
+        "cargoHash": "sha256-95DHq5GLnAqb3bbKwwaeBeKEmkfRh81ZTRaJ7L59DAg="
       }
     }
   },

nix/ext/vectorchord.nix

@@ -8,7 +8,7 @@
 let
   pname = "vchord";
   version = "1.1.0";
-  rustVersion = "1.88.0";
+  rustVersion = "1.90.0";
   pgrxVersion = "0.16.1";
 
   cargo = rust-bin.stable.${rustVersion}.default;