fix(#977): map ephemeral fnm multishell execPath to a stable fnm alias in normalizeNodePath (#992)

* fix(#977): map ephemeral fnm multishell execPath to a stable fnm alias in normalizeNodePath

Closes #977

* chore(#977): backfill changeset pr number (992)

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Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

scripts/lint-regression-test-names.allowlist.json

@@ -262,5 +262,6 @@
   "bug-950-quick-summary-status-complete.test.cjs",
   "bug-967-verify-key-links-strict-paths.test.cjs",
   "bug-974-graphify-budget-missing-value.test.cjs",
+  "bug-977-fnm-multishell-path.test.cjs",
   "bug-978-milestone-complete-force.test.cjs"
 ]