UpgradeDependencyVersion: warn on install failure instead of throwing

[Jenson3210]

Summary

When the package-manager install run by UpgradeDependencyVersion fails (typically an ERESOLVE peer-dep conflict), the recipe currently throws, aborting the entire recipe chain. That prevents later recipes — which might be the very ones that resolve the conflict, e.g. by bumping a peer-pinning library — from running at all.

The sibling AddDependency recipe already handles install failure by returning markupWarn(doc, ...) and letting the chain continue. This PR aligns the two so partial failures degrade gracefully.

Motivation

Real-world trigger: an Angular 17 project with @ng-bootstrap/ng-bootstrap@^16.0.0 (strict peer @angular/core@^17.0.0) being upgraded via a chain of UpgradeDependencyVersion calls (one for @angular/*, one for @ng-bootstrap/ng-bootstrap). Today the first failing install kills the run, and the dep graph stays in its initial inconsistent state forever. With this change, the chain continues, the marker records the failure, and a subsequent recipe can converge the graph (or a second pass of the same chain reaches fixed-point).

Diff

- import {replaceMarkerByKind} from "../../markers";
+ import {markupWarn, replaceMarkerByKind} from "../../markers";
…
  if (failureMessage) {
      const names = updateInfo.matchedDependencies.map(d => d.packageName).join(', ');
-     throw new Error(`Failed to upgrade ${names} to ${recipe.newVersion}: ${failureMessage}`);
+     return markupWarn(doc, `Failed to upgrade ${names} to ${recipe.newVersion}`, failureMessage);
  }

Tests

The two existing tests that asserted on the throw — throws when install fails for non-existent version and throws when install fails due to engine version mismatch — are reworked to assert on the MarkupWarn marker, mirroring the pattern in add-dependency.test.ts::adds warning marker when package does not exist. Renamed to adds warning marker when install fails … to match the new behaviour.

All 25 tests in upgrade-dependency-version.test.ts pass locally.

Test plan

• npm run typecheck clean
• npx vitest run test/javascript/recipes/upgrade-dependency-version.test.ts — 25/25 pass
• Run full suite in CI
• Verify the unblocked-recipe-chain behaviour against a known-failing project (Angular 17 + ng-bootstrap@16 → 18 + ng-bootstrap@17)