docs: reorganize documentation into logical categories

- Create new folders: build/, configuration/, performance/, testing/
- Move Node.js build docs to build/ folder
- Move performance docs to performance/ folder
- Move testing docs to testing/ folder
- Move configuration docs to configuration/ folder
- Remove history/ folder (archived historical docs)
- Remove planning/ folder (diary/progress tracking docs)
- Update docs/README.md to reflect new structure

Author: jdalton

docs/README.md

@@ -2,35 +2,62 @@
 
 ## Organization
 
-- **guides/** - User-facing how-to guides for building and testing
 - **architecture/** - System design documents and flow diagrams
-- **development/** - Development tools and build system docs
-- **history/** - Completed refactors and improvements (reference)
-- **planning/** - Future features and work in progress
+- **build/** - Node.js build system and patching documentation
+- **configuration/** - Shared configuration architecture
+- **development/** - Development tools and workflow
+- **guides/** - User-facing how-to guides
+- **performance/** - Performance optimization guides
 - **technical/** - Low-level implementation details
+- **testing/** - Testing strategies and guides
 
 ## Quick Links
 
-### Building & Testing
-- [Build yao-pkg binary](guides/yao-pkg-build.md)
-- [Test yao-pkg binary](guides/testing-yao-pkg.md)
-- [CI setup for yao-pkg](guides/yao-pkg-ci.md)
-
 ### Architecture
 - [Bootstrap/stub architecture](architecture/bootstrap-stub.md)
-- [Unified binary design](architecture/unified-binary.md)
-- [Stub execution flow](architecture/stub-execution.md)
 - [Repository structure](architecture/repository.md)
+- [Stub execution flow](architecture/stub-execution.md)
+- [Stub package](architecture/stub-package.md)
+- [Unified binary design](architecture/unified-binary.md)
+
+### Build System
+- [Build system summary](build/build-system-summary.md)
+- [Node.js build order](build/node-build-order-explained.md)
+- [Node.js build quick reference](build/node-build-quick-reference.md)
+- [Node.js patch creation guide](build/node-patch-creation-guide.md)
+- [Node.js patch metadata](build/node-patch-metadata.md)
+
+### Configuration
+- [Configuration migration guide](configuration/configuration-migration.md)
+- [Configuration summary](configuration/configuration-summary.md)
+- [Shared configuration architecture](configuration/shared-configuration-architecture.md)
 
 ### Development
 - [Babel plugins](development/babel-plugins.md)
-- [Platform support](development/platform-support.md)
 - [Development linking](development/linking.md)
+- [Platform support](development/platform-support.md)
+
+### Guides
+- [Build yao-pkg binary](guides/yao-pkg-build.md)
+- [CI setup for yao-pkg](guides/yao-pkg-ci.md)
+- [Test yao-pkg binary](guides/testing-yao-pkg.md)
+
+### Performance
+- [Build performance](performance/performance-build.md)
+- [CI performance](performance/performance-ci.md)
+- [Testing performance](performance/performance-testing.md)
 
 ### Technical Details
+- [Build improvements (2025-10-15)](technical/build-improvements-2025-10-15.md)
+- [Build system improvements](technical/build-system-improvements.md)
 - [Cacache format](technical/cacache-format.md)
+- [Manifest extensions](technical/manifest-extensions.md)
 - [Manifest format](technical/manifest-format.md)
-- [Patch system](technical/patch-cacache.md)
-
-### Planning & Future Work
-See [planning/README.md](planning/README.md) for planned features and work in progress.
+- [Manifest management](technical/manifest-management.md)
+- [Metadata files](technical/metadata-files.md)
+- [Patch cacache](technical/patch-cacache.md)
+
+### Testing
+- [Local testing](testing/local-testing.md)
+- [Smart test selection](testing/smart-test-selection.md)
+- [Testing custom Node.js](testing/testing-custom-node.md)