[scbrown]

Linux arm64 target selection was refused by the bootstrap installer and self-update resolver. This prepares matching archive selection while retaining checksum, executable-version, archive-membership and unsupported-target checks.

The release workflow remains unchanged in this PR. Existing releases through v0.12.1 have no Linux arm64 archive; if an asset is absent, installation refuses and preserves existing bytes. Native ARM asset production and qualification follow separately. The compatibility ledger classifies the added references to the existing caboodle alias without weakening its checker.

Before/after from the actual installer controls:

Before: explicit ARM target and detected Linux/aarch64 -> unsupported (exit 1)
After:  matching owned ARM fixture archive installs both commands
Control: absent ARM archive -> refusal, previous bytes preserved, no x86 fallback
Control: unsupported riscv64 target -> refusal

The fixtures are shell executables, not real ARM binaries. No published ARM asset or installed ARM acceptance is claimed. A public playback is unavailable; the controls are in scripts/test-install-bootstrap.py.

Validation: all five functional/test files are byte-identical to the locally qualified full change (focused Rust control plus full just check, Clippy, 379 full-suite Rust passes, 12 ignored, and native x86 release-installer fixture). This split changes only its README wording and compatibility-ledger classification; 27 current checker/mutation/bootstrap/repository controls passed. Hosted CI and the normal independent review remain pending. No release bump or publication is included.

Bead: aegis-tnr

Overlap preflight: 48d6445c50d8c823119f928dcc3ef2d34481fd1e8db4e64eec885a56d1b689ed

• PR fix(census): isolate authenticated release metadata reads #257 @ f075ddf: independent — Author Ellie explicitly separates TNR A metadata admission (PR257) from TNR C client archive selection. Fresh exact file intersection is empty. Both proceed as separate reviewed changes; retain PR257 priority and serial landing, with Ellie author-refreshing the later branch normally after the first lands. Workflow production remains held separately.