feat: support 1.88 rust 0.16.1 pgrx 0.57 wrappers

Author: samrose

flake.lock

@@ -109,10 +109,10 @@
     }
   },
   "0.16.1": {
-    "hash": "",
+    "hash": "sha256-AjoBr+/sEPdzbD0wLUNVm2syCySkGaFOFQ70TST1U9w=",
     "rust": {
       "1.88.0": {
-        "cargoHash": ""
+        "cargoHash": "sha256-uWj/V2lJa6HF2GlHX+i5RbSMZFOxZsBzOf6okKDb0j8="
       }
     }
   }

nix/cargo-pgrx/versions.json

@@ -5,7 +5,7 @@
 
 There are two types of extension package structures in our codebase:
 
-1. **Old structure (deprecated, soon to be replaced)**: Extensions like `supautils.nix` that directly define a single version
+1. **Old structure (deprecated)**: Extensions like `supautils.nix` that directly define a single version in the nix expression for the package
 2. **New structure (current standard)**: Extensions that load multiple versions from `nix/ext/versions.json`
 
 Most extensions now use the new structure, which supports multiple versions via the `versions.json` file. The instructions below cover both approaches.
@@ -143,6 +143,8 @@ These extensions use `mkPgrxExtension` and require additional Rust and pgrx vers
 
 10. **Once approved**: Update `common-nix.vars.yml` if releasing
 
+> **Need to update pgrx or Rust versions?** See [Updating cargo-pgrx Extensions](./updating-pgrx-extensions.md) for the complete guide covering pgrx version updates, Rust toolchain updates (including `nix flake update rust-overlay`), and troubleshooting.
+
 ---
 
 ## Updating an Extension (Old Structure - Deprecated)