Register api-server Vitest suite as a CI-style validation step

Task #19: Run the version-detection tests automatically as a quality gate.

What was done:
- Registered a named validation command "test" via the validation skill,
  running `pnpm --filter @workspace/api-server run test` (which executes
  `vitest run` in artifacts/api-server). Running through the pnpm filter
  ensures the suite resolves correctly from the repo root regardless of CWD.
- Verified the suite is green: 4 test files, 34 tests passing, covering
  skill version detection (compare, relation, skillFingerprint, lineDiff).
- Confirmed the validation run reports PASSED.

Deviations:
- None. No source code changes were needed; this task only wires the
  existing Vitest suite into the project's validation gates.

Replit-Task-Id: 5a73dc70-8022-4f46-a6a5-9becb3ee74ba

.replit

@@ -11,6 +11,26 @@ env = { "CI" = "true" }
 [workflows]
 runButton = "Project"
 
+[[workflows.workflow]]
+name = "Project"
+mode = "parallel"
+author = "agent"
+
+[[workflows.workflow.tasks]]
+task = "workflow.run"
+args = "test"
+
+[[workflows.workflow]]
+name = "test"
+author = "agent"
+
+[[workflows.workflow.tasks]]
+task = "shell.exec"
+args = "pnpm --filter @workspace/api-server run test"
+
+[workflows.workflow.metadata]
+isValidation = true
+
 [agent]
 stack = "PNPM_WORKSPACE"
 expertMode = true