Instrument and improve incremental workspace checks

Profile source capture, Nix evaluation/realization, resource/query checking,
and implementation builds without putting timings into immutable outputs.
Keep modular repositories; bound independent capture work, snapshot jj once
per observation, and retain final concurrent-edit and Git completeness checks.

Compose exact resource/closure/frontend/toolchain checks as memoized Nix
derivations. Preserve whole-workspace validation and the full compiler path
when no checked dependency is supplied. Share canonical Nixpkgs by content,
index workspace build contexts once, and narrow lock/driver/compiler inputs
with conservative complete-source fallback. Batch React witness checks only
when distinct source closures cannot share ambient declarations; otherwise
run the original independent TypeScript checks.

Seed local authoring toolchains with exact canonical fetch identities when
they match the selected inputs; retain store-path inputs for overrides.
Add generic correctness checks rather than permanent Reader timing/content
fixtures. Verify actual Reader edits and rejection/recovery in a private
workbench, preserving the original user's workbench and runtime.

Query checking currently caches at resource/closure boundaries, not individual
query semantic dependency boundaries. Template helper pins and reproducible
fixture snapshots follow in a separate publication change.

artifacts.nix

@@ -34,7 +34,13 @@
   group ? false,
 }:
 let
-  compiler = "${protocol}/libexec/quixos-protocol/execution-world.mjs";
+  buildTools = import ./build-tools.nix;
+  # The standalone bundle is the complete code dependency of this driver.
+  # Changes to unrelated checker CLIs must not invalidate every package group.
+  compiler = builtins.path {
+    path = "${protocol}/libexec/quixos-protocol/execution-world.mjs";
+    name = "execution-world.mjs";
+  };
   config = pkgs.writeText "camino-artifact-build.json" (
     builtins.toJSON {
       inherit
@@ -92,9 +98,15 @@ let
       serviceAdapter = ./portable-service.mjs;
     }
   );
-  compiled = pkgs.runCommand "camino-compiled-artifacts" { passthru.buildConfig = config; } ''
-    ${pkgs.nodejs_24}/bin/node ${./.}/build-artifacts.mjs ${config}
-  '';
+  compiled =
+    pkgs.runCommand "camino-compiled-artifacts"
+      {
+        passthru.buildConfig = config;
+        QUIXOS_TRACE_PROFILE = "1";
+      }
+      ''
+        ${pkgs.nodejs_24}/bin/node ${buildTools}/build-artifacts.mjs ${config}
+      '';
 in
 if group then
   compiled