fix(cli): normalize empty Windows profile before imports (#2482)

Follow-up to #2345; thanks to @gefrezim for the import-time home lookup diagnosis.

Normalize only an empty Windows USERPROFILE before runtime dependency imports, preserving all nonempty caller selections. Reuse the existing public setup dry-run regression in the Windows curated CI lane. No additional filesystem query, engine call, cache or retry.

Verified real Windows Node 24.18.0 CLI unset/empty/selected-profile controls, setup dry-run home selection and unchanged configuration, and baseline/candidate SDK stdio MCP catalogue parity. Nine related tests and static/docs checks passed. No IDA or Ghidra engine was used. Scoped resource observations and measurement limits are recorded in experiments/analysis-efficiency/windows-empty-profile.md.

Fixed the review finding and original CI package-scope ownership failure. Current-head CI is green; the unrelated MCP identity timeout passed on a failed-job rerun without changing its code or timeout. Current-head review completed with no further findings.

.github/workflows/ci.yml

@@ -509,6 +509,7 @@ jobs:
           tests/boundary/providers/native/artifactProvider.extractionCompleteness.test.ts
           tests/boundary/filesystem/setupUnavailableProvider.test.ts
           tests/boundary/filesystem/windowsNpxRegistration.test.ts
+          tests/acceptance/setup/homeDirectoryFallback.test.ts
           tests/boundary/filesystem/webScriptManifestPaths.test.ts
           tests/boundary/process/ProcessEvidence.host.test.ts
           tests/acceptance/webModuleCli.test.ts