Core Changes

• Revert "Revert "Revert "Revert "Add a --webpack flag and default --turbopack to true (#84216)"""": #84394
• Optimize isMetadataRoute function: #84409
• [ci]: split clientSegmentCache test runners off from experimental: #84440
• [Cache Components] Fix caching in generateMetadata/generateViewport: #84228
• Upgrade React from 86181134-20251001 to a757cb76-20251002: #84463
• [segment cache]: fix trailingSlash handling with output: export: #84465
• perf: Use a more aggressive retry loop for recursiveDelete: #84444
• [Cache Components] Dim logs after prerender aborts: #84153

Misc Changes

• [ci]: remove PPR-specific CI jobs: #84439
• docs: Verbose troubleshooting for unconfigured hosts: #84271
• Update Rspack production test manifest: #84398
• Add gt-next to i18n list: #84396
• [ci]: fix build-output-prerender to support segment cache env: #84467
• [ci]: fix app-static snapshots with clientSegmentCache: #84468

Credits

Huge thanks to @lukesandberg, @ztanner, @timneutkens, @icyJoseph, @unstubbable, @vercel-release-bot, @bgw, @brian-lou, and @gnoff for helping!