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The document opened with dependency installation and buried "Run From Source" between the build and release sections, so a newcomer met the MSYS2 setup before learning what the stack was. Reorder it as stack and tools, external libraries, run from source, build, release, CI, and add a clickable two-level Contents block. External libraries now list version, repository, and license type in one table, and the package-* scripts are documented for the first time. The Project Layout section is gone: it duplicated the package map in ARCHITECTURE.md and had drifted out of date, missing src/platform/filemanager. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>