fix(app-router): discard queued server actions on navigation

[anujboddu]

What?

Discard all queued server actions when a navigation/restore is dispatched so stale queued actions cannot commit state after a route change.

Why?

Issue #90467 reports queued server actions racing with navigation and clobbering state.canonicalUrl (and related router state). Previously only the currently pending action was discarded; queued actions could still run after navigation and overwrite the new route state.

How?

• Mark every queued action as discarded when a navigation/restore is dispatched.
• Keep the navigation action as the last queued action so subsequent actions queue behind it.
• Added an e2e regression test that queues multiple actions, navigates away, and asserts we remain on the destination page.

Fixes #90467

Tests

• pnpm lint-eslint packages/next/src/client/components/app-router-instance.ts test/e2e/app-dir/actions/app-action.test.ts
• Unable to run pnpm testonly-start-webpack ... locally because packages/next/dist/build/jest/jest was missing (build not generated in this environment).

[nextjs-bot]

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