chore: update all packages to latest versions

- aionui 2.1.4 -> 2.1.50
- desloppify 0.9.15 -> 1.0
- ds4 -> 2026-08-05 (b030961)
- freebuff 0.0.85 -> 0.0.142 (binary moved to GitHub releases)
- graphify 0.7.10 -> 0.9.35 (license Apache-2.0, fix sed patterns for versioned deps)
- hipengine 0.2.2 -> 0.3.0 (console script renamed to hipengine)
- kubernetes-mcp-server 0.0.62 -> 0.0.66 (requires go >= 1.26.3)
- mcp-gateway 2.11.0 -> 3.4.0 (requires rustc >= 1.95)
- omniroute 3.8.28 -> 3.8.49
- radar 1.6.1 -> 1.9.1 (drop obsolete lockfile sed patch)
- relay-free-llm -> 96e6c48, cerebras-cloud-sdk 1.67.0 -> 1.91.0
- stakpak 0.3.86 -> 0.3.88

Add nixpkgs-latest input for toolchains newer than the pinned nixpkgs.

packages/stakpak/package.nix

@@ -8,16 +8,16 @@
 
 rustPlatform.buildRustPackage rec {
   pname = "stakpak";
-  version = "0.3.86";
+  version = "0.3.88";
 
   src = fetchFromGitHub {
     owner = "stakpak";
     repo = "agent";
     rev = "v${version}";
-    hash = "sha256-k8fOgwn1Sh3Yg62ROzfKJym8AGewpZ3/2e3tHNRL7/0=";
+    hash = "sha256-rTqRxfAFQChA5fjW5VVxGThH0X7OodF1SdviMd3dK78=";
   };
 
-  cargoHash = "sha256-aa1YjyShoSNv9sC18gIx/kuAbxrNAsCE+2if8Rm2uiw=";
+  cargoHash = "sha256-jf0PqcoNtfdcDNayPNVNeWNaa0acuUJeb3CYLKN6VeA=";
 
   nativeBuildInputs = [ pkg-config ];