next.js

a85d888a - refactor: consolidate PPR into cacheComponents architecture (#88243)

refactor: consolidate PPR into cacheComponents architecture (#88243) ### What? Removes the `experimental.ppr` configuration flag and consolidates Partial Prerendering (PPR) functionality into the `cacheComponents` architecture. ### Why? Having two separate systems (PPR flag and cacheComponents) created dual code paths and complexity. PPR is now implicitly enabled when cacheComponents is enabled, simplifying the codebase. ### How? - Deleted `postpone.ts` and `ppr.ts` utility files - Removed `PrerenderStorePPR` work unit type and all PPR-specific work unit cases - Removed React.unstable_postpone-based dynamic rendering logic - Deprecated `experimental.ppr` config (kept for backwards compatibility) - Simplified build system to check only `cacheComponents` flag - Updated tests to remove PPR-specific behavior expectations This removes ~986 lines of code across 48 files.