chore(nix): regenerate Cargo.nix for unicase (improvise-cq1q.2)

Regenerated with `crate2nix generate` (0.15.0, from the dev shell). The new
file adds the unicase 2.9.0 crate and the improvise-core edge to it. It also
picks up the test-support feature edges that main's Cargo.lock already had
and Cargo.nix was missing.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VdfEGXA7aJ6ftMsCc9PJze

Cargo.nix

@@ -2668,6 +2668,7 @@ rec {
           {
             name = "improvise-protocol";
             packageId = "improvise-protocol";
+            features = [ "test-support" ];
           }
           {
             name = "improvise-wasm-client";
@@ -2751,6 +2752,11 @@ rec {
           }
         ];
         devDependencies = [
+          {
+            name = "improvise-core";
+            packageId = "improvise-core";
+            features = [ "test-support" ];
+          }
           {
             name = "improvise-protocol";
             packageId = "improvise-protocol";
@@ -2791,6 +2797,10 @@ rec {
             name = "siphasher";
             packageId = "siphasher";
           }
+          {
+            name = "unicase";
+            packageId = "unicase";
+          }
         ];
         devDependencies = [
           {
@@ -2802,7 +2812,9 @@ rec {
             packageId = "serde_json";
           }
         ];
-
+        features = {
+        };
+        resolvedDefaultFeatures = [ "test-support" ];
       };
       "improvise-formula" = rec {
         crateName = "improvise-formula";
@@ -3032,6 +3044,11 @@ rec {
             name = "improvise-core";
             packageId = "improvise-core";
           }
+          {
+            name = "improvise-protocol";
+            packageId = "improvise-protocol";
+            features = [ "test-support" ];
+          }
           {
             name = "improvise-ws-server";
             packageId = "improvise-ws-server";
@@ -6874,6 +6891,17 @@ rec {
         sha256 = "154smf048k84prsdgh09nkm2n0w0336v84jd4zikyn6v6jrqbspa";
 
       };
+      "unicase" = rec {
+        crateName = "unicase";
+        version = "2.9.0";
+        edition = "2018";
+        sha256 = "0hh1wrfd7807mfph2q67jsxqgw8hm82xg2fb8ln8cvblkwxbri6v";
+        authors = [
+          "Sean McArthur <sean@seanmonstar.com>"
+        ];
+        features = {
+        };
+      };
       "unicode-ident" = rec {
         crateName = "unicode-ident";
         version = "1.0.26";