Rebase on Go 1.22.1

[Lekensteyn]

Trivial rebase.

$ git range-diff go1.22.0..origin/cf go1.22.1..pwu/cf-1.22.1
 1:  5f4205bb70 =  1:  1da61bf0b6 Add README (#158)
 2:  8319b89c47 <  -:  ---------- VERSION: add cf tag
 -:  ---------- >  2:  412e6791f0 VERSION: add cf tag
 3:  3aca8964f3 =  3:  afa7242086 cmd/go/internal/imports, go/build: add cfgo build tag
 4:  09d2fa0fef =  4:  ea0a548ee8 .github: add docker-compose.yaml and GitHub Action for CI
 5:  aa3baed4f4 =  5:  e5515b0d01 .github: replace upstream templates and CODE_OF_CONDUCT.md
 6:  f70a6923de =  6:  b1d7991558 cmd/api: ignore CF-specific API changes
 7:  32fb8eea5e =  7:  85a53c6535 go/build: don't check dependencies of vendored circl library
 8:  848000bdf3 =  8:  4ba2d738a4 crypto/tls: expose inter-handshake timing via CFEventHandlerContextKey
 9:  acab5d0dce =  9:  0ee3c992de crypto/tls: Add hybrid post-quantum key agreements
10:  3f371b07ae = 10:  1a90cbbea3 crypto: add support for CIRCL signature schemes
11:  95a6385042 = 11:  8600abfd0d crypto/tls: implement draft-ietf-tls-subcerts-10
12:  c099eb7cd5 = 12:  0c33d9e64a crypto/tls: implement draft-ietf-tls-esni-13
13:  d52839de16 = 13:  956501e119 Set GOTOOLCHAIN to local to prevent auto-download of new Go
14:  52494648ac = 14:  84835c7d47 Add tls.Config.ClientCurveGuess to allow specifying which keyshares to send
15:  c2a040ca1d = 15:  93242326a8 Use server's preferred key agreement
16:  cf490a05dc = 16:  087d81079a Add dummy key agreement with codepoint 0xfe33 (#162)