Core Changes

• Turbopack: enable server HMR for app route handlers: #91466
• Skip loadBindings() Lightning CSS check during next start: #91538
• refactor: extract build infra and alias changes: #90422
• feat(node-streams): add config flag, define-env, and env precedence test: #90427
• Rename /_next/webpack-hmr to /_next/hmr: #91415
• ci: add node-stream test coverage workflow: #89861
• Add per-slot error attribution for instant validation using slot markers and config depth preference: #91610
• Handle encoded params further: #91627
• Fix missing route in otel spans without base-server: #91665

Misc Changes

• turbo-tasks-backend: batch find_and_schedule_dirty using for_each_task_meta: #91497
• Restructure pr-status-triage skill: merge command into skill files: #91514
• [turbopack] Use bail! instead of panic! for duplicate module ident error: #91636
• turbo-tasks-backend: batch schedule dirty tasks in aggregation_update: #91461
• Turbopack: Add importModule() support to webpack loaders: #89630
• turbo-persistence: fix mmap page alignment and improve error context in MetaFile::open_internal: #91640
• turbopack-css: demote recoverable CSS parse warnings to Warning severity: #91524
• [test] Unflake "infinite streaming fetch" test: #91645
• [test] Unflake deterministic build - changing deployment id test: #91646
• Skip CI for agent/editor config directory changes: #91622
• Update Rspack production test manifest: #91635
• [test] Increase retry timeouts for two flaky app-action tests: #91647
• Revert "ci: add node-stream test coverage workflow (#89861)"
• [test] Fix flaky url-hash tests: #91649
• Add instant validation tests for parallel slot config attribution: #91656
• [turbopack] Respect {eval:true} in worker_threads constructors: #91666

Credits

Huge thanks to @wbinnssmith, @sokra, @unstubbable, @devjiwonchoi, @timneutkens, @feedthejim, @vercel-release-bot, @gnoff, @ijjk, and @lukesandberg for helping!