fix(optimize): reject concatenateModules with cacheUnaffected again - #22744

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Reviewing files that changed from the base of the PR and between 986efee and 4fa17b2.

📒 Files selected for processing: 6

• .changeset/130-concatenation-cache-unaffected-guard.md
• lib/optimize/ModuleConcatenationPlugin.js
• test/unitCases/Compiler.unittest.js
• test/watchCases/cache/asset-concat/test.filter.js
• test/watchCases/plugins/dll-reference-plugin/test.filter.js
• test/watchCases/scope-hoisting/caching-inner-source/test.filter.js

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The module concatenation plugin now checks for cacheUnaffected during module optimization and reports the incompatibility through the hook callback. A compiler test, watch-case filters, and a changeset cover the behavior.

Changes: Concatenation cache guard

Layer / File(s)	Summary
Check compatibility during module optimization lib/optimize/ModuleConcatenationPlugin.js	The plugin moves the cacheUnaffected check to optimizeChunkModules. When module memory caches are present, it passes the incompatibility error to the hook callback and stops module optimization.
Test and document the incompatibility test/unitCases/Compiler.unittest.js, test/watchCases/cache/asset-concat/test.filter.js, test/watchCases/plugins/dll-reference-plugin/test.filter.js, test/watchCases/scope-hoisting/caching-inner-source/test.filter.js, .changeset/130-concatenation-cache-unaffected-guard.md	The compiler test checks the error. Watch-case filters identify or exclude cases that require module concatenation. The changeset records the patch.

Suggested labels: area: optimization

The incompatibility now produces a compilation error before assets are emitted in both run and watch builds. No concrete merge-blocking risk remains.

Pre-merge checks: 3 · 1

Failed checks: 1 inconclusive

Check name	Status	Explanation	Resolution
Title check		The title uses valid Conventional Commit syntax, uses the allowed type fix, and accurately describes the change. The branch prefix is not provided, so that requirement cannot be verified.	Provide the branch name or confirm that its prefix is fix. If it matches, the title passes this check.

Passed checks: 3 passed

Check name	Status	Explanation
Description Check		Check skipped - CodeRabbit’s high-level summary is enabled.
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.

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@@            Coverage Diff             @@
##             main   #22744      +/-   ##
==========================================
+ Coverage   95.98%   96.45%   +0.47%     
==========================================
  Files         778      778              
  Lines      136313   136313              
  Branches    46009    46009              
==========================================
+ Hits       130837   131481     +644     
+ Misses       5476     4832     -644     

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• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

System calls cannot be consistently instrumented, so they are not included in the measure, which understates the real cost. Please switch to the Walltime instrument to accurately measure system calls.

Measurement and system calls

• benchmark "wasm-modules-sync", scenario '{"name":"mode-development","mode":"development"}'
• benchmark "cache-filesystem-cold", scenario '{"name":"mode-development","mode":"development"}'
• benchmark "cache-filesystem", scenario '{"name":"mode-production","mode":"production"}'
• benchmark "import-meta-glob", scenario '{"name":"mode-development-rebuild","mode":"development","watch":true}'
• benchmark "no-exports-analysis", scenario '{"name":"mode-development","mode":"development"}'
• benchmark "no-minimize", scenario '{"name":"mode-development-rebuild","mode":"development","watch":true}'
• benchmark "future-defaults", scenario '{"name":"mode-development","mode":"development"}'
• benchmark "wasm-modules-sync", scenario '{"name":"mode-production","mode":"production"}'
• benchmark "devtool-eval", scenario '{"name":"mode-development-rebuild","mode":"development","watch":true}'
• benchmark "many-chunks-esm", scenario '{"name":"mode-development-rebuild","mode":"development","watch":true}'
• …and 98 more

The flamegraph could not be generated because too much time was spent in runtime internals, making the visualization not useful for performance analysis.

• benchmark "wasm-modules-sync", scenario '{"name":"mode-production","mode":"production"}'
• benchmark "context-esm", scenario '{"name":"mode-production","mode":"production"}'
• benchmark "asset-modules-inline", scenario '{"name":"mode-production","mode":"production"}'
• benchmark "context-commonjs", scenario '{"name":"mode-production","mode":"production"}'
• benchmark "asset-modules-bytes", scenario '{"name":"mode-production","mode":"production"}'
• benchmark "concatenate-modules", scenario '{"name":"mode-production","mode":"production"}'
• benchmark "common-libs", scenario '{"name":"mode-production","mode":"production"}'
• benchmark "devtool-eval", scenario '{"name":"mode-production","mode":"production"}'
• benchmark "asset-modules-resource", scenario '{"name":"mode-production","mode":"production"}'
• benchmark "module-unsafe-cache", scenario '{"name":"mode-production","mode":"production"}'
• …and 19 more

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate