chore(v2): vendor dependencies for offline/China builds

go mod vendor pins onnxruntime_go v1.12.1, Gio and the rest into v2/vendor
so go run/build work without hitting proxy.golang.org (blocked/slow in
China). Verified: CGO_ENABLED=1 go build -mod=vendor ./internal/spike and
GOOS=windows go build -mod=vendor ./internal/ui both pass.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

v2/vendor/gioui.org/io/semantic/semantic.go

@@ -0,0 +1,91 @@
+// SPDX-License-Identifier: Unlicense OR MIT
+
+// Package semantic provides operations for semantic descriptions of a user
+// interface, to facilitate presentation and interaction in external software
+// such as screen readers.
+//
+// Semantic descriptions are organized in a tree, with clip operations as
+// nodes. Operations in this package are associated with the current semantic
+// node, that is the most recent pushed clip operation.
+package semantic
+
+import (
+	"gioui.org/internal/ops"
+	"gioui.org/op"
+)
+
+// LabelOp provides the content of a textual component.
+type LabelOp string
+
+// DescriptionOp describes a component.
+type DescriptionOp string
+
+// ClassOp provides the component class.
+type ClassOp int
+
+const (
+	Unknown ClassOp = iota
+	Button
+	CheckBox
+	Editor
+	RadioButton
+	Switch
+)
+
+// SelectedOp describes the selected state for components that have
+// boolean state.
+type SelectedOp bool
+
+// EnabledOp describes the enabled state.
+type EnabledOp bool
+
+func (l LabelOp) Add(o *op.Ops) {
+	data := ops.Write1String(&o.Internal, ops.TypeSemanticLabelLen, string(l))
+	data[0] = byte(ops.TypeSemanticLabel)
+}
+
+func (d DescriptionOp) Add(o *op.Ops) {
+	data := ops.Write1String(&o.Internal, ops.TypeSemanticDescLen, string(d))
+	data[0] = byte(ops.TypeSemanticDesc)
+}
+
+func (c ClassOp) Add(o *op.Ops) {
+	data := ops.Write(&o.Internal, ops.TypeSemanticClassLen)
+	data[0] = byte(ops.TypeSemanticClass)
+	data[1] = byte(c)
+}
+
+func (s SelectedOp) Add(o *op.Ops) {
+	data := ops.Write(&o.Internal, ops.TypeSemanticSelectedLen)
+	data[0] = byte(ops.TypeSemanticSelected)
+	if s {
+		data[1] = 1
+	}
+}
+
+func (e EnabledOp) Add(o *op.Ops) {
+	data := ops.Write(&o.Internal, ops.TypeSemanticEnabledLen)
+	data[0] = byte(ops.TypeSemanticEnabled)
+	if e {
+		data[1] = 1
+	}
+}
+
+func (c ClassOp) String() string {
+	switch c {
+	case Unknown:
+		return "Unknown"
+	case Button:
+		return "Button"
+	case CheckBox:
+		return "CheckBox"
+	case Editor:
+		return "Editor"
+	case RadioButton:
+		return "RadioButton"
+	case Switch:
+		return "Switch"
+	default:
+		panic("invalid ClassOp")
+	}
+}