fix(evals): add missing owner to negative trigger tests

Six negative-trigger prompts across six case files declared no `owner`,
so per evals/README.md and scripts/run-evals.js they could only pass
vacuously (skip the pairwise routing assertion) instead of asserting
that the correct skill actually outranks the tested one.

Added owner for the prompts where a real, unambiguous owner exists and
verified against scripts/run-evals.js that it outranks the tested skill
with a non-zero score:

- code-simplification: "Add a feature flag system to the app" -> incremental-implementation
- deprecation-and-migration: "Add dark mode to the settings page" -> frontend-ui-engineering
- doubt-driven-development: "Write the changelog entry for the release" -> git-workflow-and-versioning
- frontend-ui-engineering: "Tag and publish the release" -> git-workflow-and-versioning
- planning-and-task-breakdown: "Encode the output so it is safe against XSS" -> security-and-hardening
- using-agent-skills: "Make the modal accessible for keyboard users" -> frontend-ui-engineering

Left four other owner-less negatives untouched (doubt-driven-development's
"Format this file with prettier", git-workflow-and-versioning's "Add a
loading spinner to the submit button", observability-and-instrumentation's
"Draft the PRD for the referral program", and shipping-and-launch's "Why
is this function so slow on large inputs?") because no skill scores above
zero against them under the current TF-IDF scorer, so declaring an owner
there would either fail CI or force a misleading pick.

Verified: node scripts/run-evals.js still passes (127 checks, 0 errors,
86% rank-1) and node scripts/validate-commands.js passes.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

evals/cases/code-simplification.json

@@ -17,7 +17,8 @@
     ],
     "negative": [
       {
-        "prompt": "Add a feature flag system to the app"
+        "prompt": "Add a feature flag system to the app",
+        "owner": "incremental-implementation"
       },
       {
         "prompt": "Diagnose why the build broke overnight",

evals/cases/deprecation-and-migration.json

@@ -17,7 +17,8 @@
     ],
     "negative": [
       {
-        "prompt": "Add dark mode to the settings page"
+        "prompt": "Add dark mode to the settings page",
+        "owner": "frontend-ui-engineering"
       },
       {
         "prompt": "Why is this test flaky on CI?",

evals/cases/doubt-driven-development.json

@@ -20,7 +20,8 @@
         "prompt": "Format this file with prettier"
       },
       {
-        "prompt": "Write the changelog entry for the release"
+        "prompt": "Write the changelog entry for the release",
+        "owner": "git-workflow-and-versioning"
       }
     ]
   },

evals/cases/frontend-ui-engineering.json

@@ -29,7 +29,8 @@
         "owner": "performance-optimization"
       },
       {
-        "prompt": "Tag and publish the release"
+        "prompt": "Tag and publish the release",
+        "owner": "git-workflow-and-versioning"
       }
     ]
   },

evals/cases/planning-and-task-breakdown.json

@@ -21,7 +21,8 @@
         "owner": "debugging-and-error-recovery"
       },
       {
-        "prompt": "Encode the output so it is safe against XSS"
+        "prompt": "Encode the output so it is safe against XSS",
+        "owner": "security-and-hardening"
       }
     ]
   },

evals/cases/using-agent-skills.json

@@ -21,7 +21,8 @@
         "owner": "debugging-and-error-recovery"
       },
       {
-        "prompt": "Make the modal accessible for keyboard users"
+        "prompt": "Make the modal accessible for keyboard users",
+        "owner": "frontend-ui-engineering"
       }
     ]
   },