Implement the intent core

Details (original message):
Implement the intent core, conformance suite, catalog alignment, examples, and the intentctl diagnostics CLI.

examples/example_test.go

@@ -0,0 +1,71 @@
+// Package examples 演示消费方最小接入：守卫内容以 Go 内置注册并放入保护域，
+// 业务意图来自嵌入的 JSON overlay；识别、槽位与诊断全部走公开 API。
+package examples
+
+import (
+	"context"
+	"embed"
+	"testing"
+
+	"agent-intent/conformance"
+	"agent-intent/intent"
+)
+
+//go:embed specs/*.json
+var specFS embed.FS
+
+// guardSpec 守卫内容属于宿主内置资产：放进保护域后 overlay 无法覆盖或禁用。
+func guardSpec() intent.IntentSpec {
+	return intent.IntentSpec{
+		ID:       "guard.config_change",
+		Domain:   "guard",
+		Version:  1,
+		Priority: 1000,
+		Matcher:  intent.MatchSpec{IncludesAny: []string{"系统配置", "网关", "改密码"}},
+		Risk:     intent.RiskHigh,
+		Handler:  "refuse.and_guide",
+	}
+}
+
+func build(t *testing.T) (*intent.Registry, intent.Recognizer) {
+	t.Helper()
+	b := intent.NewRegistryBuilder(intent.Options{
+		ProtectedDomains: []string{"guard"},
+		GuardDomains:     []string{"guard"},
+	})
+	if err := b.Register(guardSpec()); err != nil {
+		t.Fatal(err)
+	}
+	reg, err := b.BuildFS(context.Background(), specFS, "specs")
+	if err != nil {
+		t.Fatal(err)
+	}
+	return reg, intent.NewRecognizer(intent.Options{}, nil, nil)
+}
+
+func TestEndToEnd(t *testing.T) {
+	reg, rec := build(t)
+	snap := reg.Snapshot()
+
+	conformance.Run(t, rec, snap, []conformance.Case{
+		{Name: "guard_intercepts", Input: "帮我改一下系统网关地址", ExpectBranch: intent.BranchGuardHit, ExpectTopID: "guard.config_change"},
+		{Name: "matched_with_slot", Input: "查询任务 42 的进度", ExpectBranch: intent.BranchMatched, ExpectTopID: "demo.run.status_query", ExpectSlots: map[string]string{"run_id": "42"}},
+		{Name: "restart_requires_confirm", Input: "把任务重启一下", ExpectBranch: intent.BranchMatched, ExpectTopID: "demo.run.restart"},
+		{Name: "free_falls_back", Input: "帮我写一份周报", ExpectBranch: intent.BranchFallback},
+	})
+
+	// 宿主用 Top 的元数据决定后续动作（通道、确认策略、动作键）。
+	res, err := rec.Recognize(context.Background(), "把任务重启一下", snap)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !res.Top.RequiresConfirm || res.Top.Handler != "taskrun.restart" || res.Top.Risk != intent.RiskMedium {
+		t.Fatalf("top metadata: %+v", res.Top)
+	}
+
+	// 诊断：Explain 给出守卫与规则两阶段的完整裁决轨迹。
+	trace := snap.Explain("怎么配置查询进度")
+	if trace.Branch != intent.BranchFallback {
+		t.Fatalf("explain branch: %+v", trace)
+	}
+}

examples/specs/demo.json

@@ -0,0 +1,28 @@
+{
+  "intents": [
+    {
+      "id": "demo.run.status_query",
+      "domain": "demo",
+      "version": 1,
+      "description": "查询任务运行进度",
+      "matcher": {"includes_any": ["进度", "状态"], "excludes_any": ["配置"]},
+      "slots": [
+        {"key": "run_id", "required": false, "pattern": "(?:run|任务)[:# ]*([A-Za-z0-9-]+)", "group": 1}
+      ],
+      "confidence": {"base": 0.8, "threshold": 0.7},
+      "handler": "taskrun.query_status",
+      "metadata": {"channel": "dialogue"}
+    },
+    {
+      "id": "demo.run.restart",
+      "domain": "demo",
+      "version": 1,
+      "description": "重启任务",
+      "matcher": {"includes_any": ["重启"], "includes_all": ["任务"]},
+      "confidence": {"base": 0.75, "threshold": 0.7},
+      "risk": "medium",
+      "requires_confirm": true,
+      "handler": "taskrun.restart"
+    }
+  ]
+}