dolt: 1.59.10 -> 1.81.2

Since v1.59.13, dolt depends on dolthub/go-icu-regex which requires
ICU C headers (unicode/uregex.h) at build time. The nixpkgs-update bot
has failed to update dolt for ~21 consecutive weeks due to this missing
dependency. Adding icu to buildInputs unblocks automated updates.

Update dolt to latest version compatible with nixpkgs Go 1.25.5.
v1.81.3+ requires Go >= 1.25.6 which is not yet in nixpkgs.

Build verified via `nix-build -A dolt` in Docker.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

pkgs/by-name/do/dolt/package.nix

@@ -1,26 +1,29 @@
 {
   fetchFromGitHub,
+  icu,
   lib,
   buildGoModule,
 }:
 
 buildGoModule (finalAttrs: {
   pname = "dolt";
-  version = "1.59.10";
+  version = "1.81.2";
 
   src = fetchFromGitHub {
     owner = "dolthub";
     repo = "dolt";
     tag = "v${finalAttrs.version}";
-    hash = "sha256-DfocUOHpPdNeMcL7kVm7ggm2cVgWp/ifvCFyFosxhcs=";
+    hash = "sha256-dL6WJvApRGC8ADFowms81YbJpLbbTyNQfI/RIotgTdc=";
   };
 
   modRoot = "./go";
   subPackages = [ "cmd/dolt" ];
-  vendorHash = "sha256-yZ+q4KNfIiR2gpk10dpZOMiEN3V/Lk/pzhgaqp7lKag=";
+  vendorHash = "sha256-wufwBlRiRiNVZgkBFRqZIB6vNeWBBaCDdV2tcynhatk=";
   proxyVendor = true;
   doCheck = false;
 
+  buildInputs = [ icu ];
+
   meta = {
     description = "Relational database with version control and CLI a-la Git";
     mainProgram = "dolt";