projection: begin the exact-path public epoch

The public tree and its history contain only the listed paths. Earlier projection history remains preserved internally.

Source-Sha: 913fde029b935671833254797f0f20f1eb9fabba

Policy-Sha: 913fde029b935671833254797f0f20f1eb9fabba

Tree-Digest: 180ae530c1058a2a5c89837bdce2d323ae83e669e38590ca72e75b8d92b7262f

agent/internal/recovery/panic.go

@@ -0,0 +1,66 @@
+// Package recovery provides panic recovery mechanisms for the agent
+// [TD-002] Phase 0 - Panic Recovery implementation
+package recovery
+
+import (
+	"fmt"
+	"log"
+	"runtime/debug"
+)
+
+// RecoveryHandler is a function that handles recovered panics
+type RecoveryHandler func(component string, err interface{}, stack []byte)
+
+// defaultHandler logs the panic with stack trace
+var defaultHandler RecoveryHandler = func(component string, err interface{}, stack []byte) {
+	log.Printf("[CRITICAL] [%s] panic_recovered error=%q", component, err)
+	log.Printf("[CRITICAL] [%s] stack_trace=%s", component, string(stack))
+}
+
+// SetHandler sets a custom recovery handler
+func SetHandler(handler RecoveryHandler) {
+	defaultHandler = handler
+}
+
+// Recover wraps a function with panic recovery
+// Usage: defer recovery.Recover("component_name")
+func Recover(component string) {
+	if r := recover(); r != nil {
+		stack := debug.Stack()
+		defaultHandler(component, r, stack)
+	}
+}
+
+// RecoverWithCallback wraps a function with panic recovery and custom callback
+func RecoverWithCallback(component string, callback func(interface{}, []byte)) {
+	if r := recover(); r != nil {
+		stack := debug.Stack()
+		defaultHandler(component, r, stack)
+		if callback != nil {
+			callback(r, stack)
+		}
+	}
+}
+
+// SafeCall executes a function with panic recovery, returns error on panic
+func SafeCall(component string, fn func() error) (err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			stack := debug.Stack()
+			defaultHandler(component, r, stack)
+			err = fmt.Errorf("panic in %s: %v", component, r)
+		}
+	}()
+	return fn()
+}
+
+// SafeCallVoid executes a void function with panic recovery
+func SafeCallVoid(component string, fn func()) {
+	defer func() {
+		if r := recover(); r != nil {
+			stack := debug.Stack()
+			defaultHandler(component, r, stack)
+		}
+	}()
+	fn()
+}