perf: avoid unnecessary data router re-renders

[brophdawg11]

Reduce unnecessary Data and Framework Mode route component re-renders by separating route IDs, active router state, route data, pending navigation state, and fetcher state into stable React contexts.

• Keep parent route components stable when only a descendant location changes.
• Avoid notifying useLoaderData consumers when no loader data changed.
• Avoid notifying active-state consumers when navigation enters a pending state, while preserving updates for useNavigation, useRevalidator, NavLink, and unstable_useRouterState.
• Avoid notifying useMatches and useRoute consumers when fetchers update, while preserving updates for useFetcher and useFetchers.

[github-actions]

Preview Build Available

Preview builds have been created for this PR. You can install react-router using:

pnpm install "remix-run/react-router#preview/pr-15376&path:packages/react-router"

And/or install other packages via:

pnpm install "remix-run/react-router#preview/pr-15376&path:packages/react-router-dev"
pnpm install "remix-run/react-router#preview/pr-15376&path:packages/react-router-express"
pnpm install "remix-run/react-router#preview/pr-15376&path:packages/react-router-node"
pnpm install "remix-run/react-router#preview/pr-15376&path:packages/react-router-serve"

These preview builds will be updated automatically as you push new commits.

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Type	Change
patch	Avoid unnecessary route component re-renders when unrelated data router state changes