Add passkey (WebAuthn) authentication support

Enable passwordless login via passkeys as an alternative to password auth.
Users register passkeys from Settings; the login page offers both options.
WebAuthn is optional — only active when WEBAUTHN_RP_ID and WEBAUTHN_ORIGIN
env vars are set.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/go.sum b/go.sum
index b34a475..f82d427 100644
--- a/go.sum
+++ b/go.sum
@@ -20,6 +20,8 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
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@@ -27,11 +29,21 @@ github.com/go-logr/logr v1.4.3 h1:CjnDlHq8ikf6E492q6eKboGOC0T8CDaOvkHCIg8idEI=
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+github.com/go-webauthn/x v0.1.26 h1:eNzreFKnwNLDFoywGh9FA8YOMebBWTUNlNSdolQRebs=
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+github.com/google/go-tpm v0.9.6 h1:Ku42PT4LmjDu1H5C5ISWLlpI1mj+Zq7sPGKoRw2XROA=
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@@ -52,6 +64,8 @@ github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZb
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
 github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
+github.com/x448/float16 v0.8.4 h1:qLwI1I70+NjRFUR3zs1JPUCgaCXSh3SW62uAKT1mSBM=
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@@ -67,6 +81,8 @@ go.opentelemetry.io/otel/sdk/metric v1.38.0 h1:aSH66iL0aZqo//xXzQLYozmWrXxyFkBJ6
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+go.uber.org/mock v0.6.0 h1:hyF9dfmbgIX5EfOdasqLsWD6xqpNZlXblLB/Dbnwv3Y=
+go.uber.org/mock v0.6.0/go.mod h1:KiVJ4BqZJaMj4svdfmHM0AUx4NJYO8ZNpPnZn1Z+BBU=
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