Hash the hook with normalized line endings: CRLF checkouts attested as edited (0.22.0)

[davidcrowe]

What happened

Two Windows installs of 0.21.0 on 2026-09-17 reported different hook hashes for the same unmodified bin/govern.mjs. The first (LF) seeded the registry's first-seen hash for 0.21.0. The second machine had Git for Windows at its default core.autocrlf=true, checked the file out as CRLF, and was flagged hook.attestation.hash_mismatch at its first session start, with a founder page for an edit that never happened.

Verified byte for byte against origin/main:

File	sha256
bin/govern.mjs, LF	cedbe165… = registry first-seen for 0.21.0
same file, CRLF	d4c90fe1… = the flagged machine's reported hash

Every default-settings Windows install of every version attests as an edited hook unless it happens to be the first machine seen for that version. The trust-on-first-use baseline is set by whichever OS attests first.

Change

• bin/govern.mjs: sha256FileHex strips CRLF to LF before hashing. Byte-transparent latin1 round trip, so an LF file hashes exactly as before and no existing first-seen hash changes. Lone CRs are kept.
• lib/attestation.mjs: normalizeEol and sha256FileHex mirror the inline logic so the tests pin it.
• .gitattributes: eol=lf for every text file, so future checkouts do not convert in the first place.
• Version 0.22.0 in plugin.json, .claude-plugin/marketplace.json, PLUGIN_VERSION.

Tests

• Unit: CRLF and LF copies hash identically; the committed hook is LF and unchanged by normalization; a lone CR is preserved.
• End to end: a CRLF copy of the real hook, run at SessionStart against a stub gateway, reports the LF release hash, and the lib copy agrees with the inline copy.
• Full suite: 243 pass, 0 fail. node --check and validate-manifest clean.

After merge

• Set platformHookRegistry/claude-code-plugin.latest to 0.22.0 so 0.21.0 machines get the stale-hook notice.
• Existing 0.21.0 CRLF checkouts keep flagging once a day until they update. The registry's 0.21.0 entry stays as is.