feat(orchestration/audit): 子代理上下文可审计查询（全量/尾部/关键词定位）+ 主代理代审授权（审计日志+小字）

internal/runtime/orchestration/audit/context.go

@@ -0,0 +1,122 @@
+package audit
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"strings"
+
+	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/model"
+)
+
+// ErrQueryEmpty is returned by ContextAuditor.Keyword when the query is empty
+// or blank. Use errors.Is to test for it.
+var ErrQueryEmpty = errors.New("audit: query is empty")
+
+// contextRadius is how many messages on each side of a keyword hit are included
+// in the surrounding window (one above and one below).
+const contextRadius = 1
+
+// Located describes a single keyword match within a subagent context.
+type Located struct {
+	// Line is the 1-based index of the matched message in the full context.
+	Line int
+	// Surrounding is a window centered on the matched message: the message
+	// immediately before it, the matched message, and the message immediately
+	// after it, clamped at the context boundaries. It always contains the
+	// matched message.
+	Surrounding []model.Message
+}
+
+// ContextAuditor provides read-only, traceable access to a subagent's context.
+// It snapshots the message list at construction so later mutation by the caller
+// does not change what the auditor reports. It is a value type that holds no
+// storage or policy; the orchestral layer decides which context to inspect.
+type ContextAuditor struct {
+	messages []model.Message
+}
+
+// NewContextAuditor snapshots messages so subsequent caller mutations do not
+// affect the auditor. A nil input is allowed and yields an empty context.
+func NewContextAuditor(messages []model.Message) ContextAuditor {
+	cp := make([]model.Message, len(messages))
+	copy(cp, messages)
+	return ContextAuditor{messages: cp}
+}
+
+// Full returns a defensive copy of the entire context.
+func (a ContextAuditor) Full() []model.Message {
+	cp := make([]model.Message, len(a.messages))
+	copy(cp, a.messages)
+	return cp
+}
+
+// Tail returns the last n messages of the context in their original order.
+//
+// n <= 0 yields an empty, non-nil slice; n >= len returns a copy of the full
+// context. The result is a defensive copy.
+func (a ContextAuditor) Tail(n int) []model.Message {
+	if n <= 0 {
+		return []model.Message{}
+	}
+	if n >= len(a.messages) {
+		return a.Full()
+	}
+	start := len(a.messages) - n
+	out := make([]model.Message, n)
+	copy(out, a.messages[start:])
+	return out
+}
+
+// Keyword locates the first message whose text contains query, using a
+// case-insensitive substring match against the message's text parts (image
+// payloads are ignored). It returns the message's 1-based index and a
+// surrounding window, or nil, nil when there is no match.
+//
+// It returns ErrQueryEmpty for a blank query and wraps ctx.Err() when ctx is
+// canceled. Only the earliest match is reported.
+func (a ContextAuditor) Keyword(ctx context.Context, query string) (*Located, error) {
+	if strings.TrimSpace(query) == "" {
+		return nil, fmt.Errorf("%w: query is blank", ErrQueryEmpty)
+	}
+	if err := ctx.Err(); err != nil {
+		return nil, fmt.Errorf("audit: keyword: %w", err)
+	}
+	q := strings.ToLower(query)
+	for i, m := range a.messages {
+		if strings.Contains(strings.ToLower(messageText(m)), q) {
+			return &Located{Line: i + 1, Surrounding: a.window(i)}, nil
+		}
+	}
+	return nil, nil
+}
+
+// window returns up to 2*contextRadius+1 messages centered on index i, clamped
+// to the context boundaries.
+func (a ContextAuditor) window(i int) []model.Message {
+	lo := i - contextRadius
+	hi := i + contextRadius
+	if lo < 0 {
+		lo = 0
+	}
+	if hi >= len(a.messages) {
+		hi = len(a.messages) - 1
+	}
+	if lo > hi {
+		return nil
+	}
+	out := make([]model.Message, 0, hi-lo+1)
+	out = append(out, a.messages[lo:hi+1]...)
+	return out
+}
+
+// messageText returns the concatenated text of a message's text parts.
+func messageText(m model.Message) string {
+	var b strings.Builder
+	for _, c := range m.Content {
+		if c.Type == model.ContentTypeText && c.Text != "" {
+			b.WriteString(c.Text)
+		}
+	}
+	return b.String()
+}