sce v0.4.0-pre-alpha-v7

CLI release assets

• Canonical sce archives are published as sce-v<version>-<target-triple>.tar.gz
• Per-archive SHA-256 checksum files are published as sce-v<version>-<target-triple>.tar.gz.sha256
• Combined artifact metadata is published as sce-v<version>-release-manifest.json
• Combined artifact manifest signatures are published as sce-v<version>-release-manifest.json.sig
• Combined checksums are published as sce-v<version>-SHA256SUMS
• The npm package tarball is published as sce-v<version>-npm.tgz
• Flatpak source-built packaging metadata is published as sce-v<version>-flatpak-manifest.tar.gz, with matching .sha256 and .json metadata assets; this is not a prebuilt Flatpak app or Flathub publication.
• Flatpak source-built .flatpak bundles are published as sce-v<version>-x86_64.flatpak and sce-v<version>-aarch64.flatpak, with matching .sha256 and .json metadata assets; install directly with flatpak install --user <url>.

What's Changed

• config: Reduce workflow instruction duplication by @davidabram in #270
• Setup: Handle invalid config and confirm optional behavior settings by @ivke995 in #264
• Claude bridge-session model fix by @davidabram in #265
• runtime: Classify top level sce command failures with typed user-error catalog by @stefanskoricdev in #223
• Remove checkoutID by @davidabram in #279

Full Changelog: v0.4.0-pre-alpha-v6...v0.4.0-pre-alpha-v7