feat: add axon CLI for pub/sub; fix relay hijack context bug

- cmd/axon: new CLI module with keygen, pub, and req subcommands
  - keygen: generate Ed25519 keypair, print hex seed and pubkey
  - pub: sign and publish an event; accepts --kind, --content, --tag
  - req: query/stream events as JSON lines; accepts --kind, --author,
    --tag, --since, --until, --limit, --stream
  - key loaded from --key flag or AXON_KEY env var

- relay/websocket: add Dial() for client-side WebSocket handshake
  (ws:// and wss://, RFC 6455 masking via client:true)

- relay/server: fix broken-pipe on auth by switching hijacked conn
  goroutine from r.Context() to context.Background(); r.Context() is
  cancelled by net/http immediately after Hijack is called

1 files changed, 20 insertions, 0 deletions

diff --git a/cmd/axon/go.mod b/cmd/axon/go.mod
new file mode 100644
index 0000000..2f26fca
--- /dev/null
+++ b/cmd/axon/go.mod
@@ -0,0 +1,20 @@
+module axon/cli
+
+go 1.25.5
+
+require (
+        axon v0.0.0
+        axon/relay v0.0.0
+        github.com/vmihailenco/msgpack/v5 v5.4.1
+)
+
+require (
+        github.com/vmihailenco/tagparser/v2 v2.0.0 // indirect
+        golang.org/x/crypto v0.48.0 // indirect
+        golang.org/x/sys v0.41.0 // indirect
+)
+
+replace (
+        axon => ../../
+        axon/relay => ../../relay
+)