Add daemon RPC support for gate commands (bd-likt)

- Add gate operation constants (OpGateCreate, OpGateList, OpGateShow,
  OpGateClose, OpGateWait) to protocol.go
- Add Gate*Args and Gate*Result types to protocol.go
- Add gate handler methods (handleGateCreate, handleGateList,
  handleGateShow, handleGateClose, handleGateWait) to server_issues_epics.go
- Register gate handlers in handleRequest switch
- Add gate client methods (GateCreate, GateList, GateShow, GateClose,
  GateWait) to client.go
- Update cmd/bd/gate.go to use daemon client when available, falling
  back to direct store access

Gate commands now work with the daemon, eliminating the need for
--no-daemon flag.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

internal/rpc/client.go

@@ -395,6 +395,33 @@ func (c *Client) EpicStatus(args *EpicStatusArgs) (*Response, error) {
 	return c.Execute(OpEpicStatus, args)
 }
 
+// Gate operations (bd-likt)
+
+// GateCreate creates a gate via the daemon
+func (c *Client) GateCreate(args *GateCreateArgs) (*Response, error) {
+	return c.Execute(OpGateCreate, args)
+}
+
+// GateList lists gates via the daemon
+func (c *Client) GateList(args *GateListArgs) (*Response, error) {
+	return c.Execute(OpGateList, args)
+}
+
+// GateShow shows a gate via the daemon
+func (c *Client) GateShow(args *GateShowArgs) (*Response, error) {
+	return c.Execute(OpGateShow, args)
+}
+
+// GateClose closes a gate via the daemon
+func (c *Client) GateClose(args *GateCloseArgs) (*Response, error) {
+	return c.Execute(OpGateClose, args)
+}
+
+// GateWait adds waiters to a gate via the daemon
+func (c *Client) GateWait(args *GateWaitArgs) (*Response, error) {
+	return c.Execute(OpGateWait, args)
+}
+
 // cleanupStaleDaemonArtifacts removes stale daemon.pid file when socket is missing and lock is free.
 // This prevents stale artifacts from accumulating after daemon crashes.
 // Only removes pid file - lock file is managed by OS (released on process exit).