Downloads tab: core libs by release tag, modular libs with per-platform status

[danoli3]

Summary

• oF Menu tab is now downloads and always visible (was Advanced-only)
• Core libraries: pick an apothecary release (latest, v12.1.1, v12.1.0, ...) + platform, runs scripts/<platform>/download_libs.sh -t <tag> and streams to the console. Replaces the old update-libs button, which did nothing on an existing install since of.sh skips redownload when non-interactive
• Core source picker: Apothecary / ofLibs (ofWorks/ofLibs) / Archive (libs.danoli3.com), each with its own release list. ofLibs + archive run downloadOfLibs / downloadArchiveRelease from the checkout's scripts/dev/lib_sources.sh, same as of.sh. Archive asks before running since it replaces whole libs/ folders incl. libs/openFrameworks
• Modular libraries: lists oF_<lib>_<target> packages from latest-modular (Poco, Dawn, OpenSSL, curl, fmt, ...) per target, select + download individually
  • SHA-256 checked against the GitHub release asset digest before extracting
  • installs into libs/<lib> or the owning addon (poco -> addons/ofxPoco/libs/poco, same table as download_libs.sh), keeps existing xcframework Info.plist for osx like download_libs.sh does
  • status column shows every platform the lib is installed for (macOS iOS tvOS Emscripten ...), reading xcframework slices under lib/macos, current target highlighted
• Readable labels: core platforms macOS (OSX only), macOS (including iOS, tvOS, catOS), Windows (Visual Studio) ...; targets macOS (OSX) (x86_64 / arm64), iOS (arm64), Linux (arm64) gcc14 ...
• osx platform label OS X (Xcode) -> macOS (OSX) (Xcode) (settings store the key, so no migration)
• Page now scrolls clear of the console at any console height (bottom padding was on body, which doesn't grow, and fixed at 100px)
• Strings added for all 9 locales
  
  

Notes

• latest-modular has no vs packages yet, so Windows shows an empty modular list until those are published
• Core download still needs bash on Windows (same as the old of.sh button); modular uses the built-in tar
• scripts/dev/download_libs.sh (OF repo) passes a literal 1 to the downloader for -s, so -s isn't used here; progress-bar redraws are stripped GUI-side instead

Test plan

• ofLibs v1.0 osx via lib_sources.sh into a scratch OF dir: 16 libs SHA-256 verified (brotli has no macos build upstream); source switching refills release/platform lists live
• Real downloads via the main-process handlers into a scratch OF dir: poco -> addons/ofxPoco/libs/poco, fmt -> libs/fmt, both SHA-256 verified; missing asset reports cleanly
• Core handler passes -t v12.1.1 for tags, no flag for latest, clean error for a missing platform script
• Live Electron launch: tab loads releases, per-platform status matches disk, selection/button state, console resized to 500px still scrolls to the bottom buttons