Switch remote deploy to vendored source builds

Move remote deployment to a vendored source bundle built on the target host via Docker so redeploys no longer require local cross-compilation or host Go installation.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

vendor/golang.org/x/net/http2/timer.go

@@ -0,0 +1,20 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+package http2
+
+import "time"
+
+// A timer is a time.Timer, as an interface which can be replaced in tests.
+type timer = interface {
+	C() <-chan time.Time
+	Reset(d time.Duration) bool
+	Stop() bool
+}
+
+// timeTimer adapts a time.Timer to the timer interface.
+type timeTimer struct {
+	*time.Timer
+}
+
+func (t timeTimer) C() <-chan time.Time { return t.Timer.C }