feat: wire external rules pipeline into ingress and dispatch

- Add DispatchContext field to Task model for rule metadata storage
- Add BlocklistEmails config (BLOCKLIST_EMAILS env var)
- Wire rules.Pipeline into IMAPWatcher, replacing inline whitelist check
- Pass rule metadata through DispatchContext to OpenClaw dispatch
- Remove isWhitelisted method (now handled by WhitelistRule)

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

internal/mail/imap.go

@@ -3,6 +3,7 @@ package mail
 import (
 	"context"
 	"crypto/tls"
+	"encoding/json"
 	"fmt"
 	"io"
 	"log/slog"
@@ -21,6 +22,7 @@ import (
 	"thuanle.me/claw-email-bridge/internal/config"
 	"thuanle.me/claw-email-bridge/internal/database"
 	"thuanle.me/claw-email-bridge/internal/logging"
+	"thuanle.me/claw-email-bridge/internal/rules"
 )
 
 // IMAPWatcher monitors an IMAP mailbox via IDLE and processes new emails.
@@ -32,6 +34,8 @@ type IMAPWatcher struct {
 	dialIMAP         func(addr string, options *imapclient.Options) (*imapclient.Client, error)
 	dialIMAPViaProxy func(addr, proxyURL string, options *imapclient.Options) (*imapclient.Client, error)
 
+	rules *rules.Pipeline
+
 	// onReceived is called after a task is saved as RECEIVED.
 	// This will be wired to the OpenClaw dispatch in a future step.
 	OnReceived func(task *database.Task)
@@ -57,11 +61,20 @@ var socks5DialerFactory = proxy.SOCKS5
 
 // NewIMAPWatcher creates a new IMAP watcher.
 func NewIMAPWatcher(cfg *config.Config, db *gorm.DB) *IMAPWatcher {
+	var externalRules []rules.Rule
+	if len(cfg.WhitelistEmails) > 0 {
+		externalRules = append(externalRules, rules.NewWhitelistRule(cfg.WhitelistEmails))
+	}
+	if len(cfg.BlocklistEmails) > 0 {
+		externalRules = append(externalRules, rules.NewBlocklistRule(cfg.BlocklistEmails))
+	}
+
 	return &IMAPWatcher{
 		cfg:              cfg,
 		db:               db,
 		dialIMAP:         imapclient.DialTLS,
 		dialIMAPViaProxy: dialTLSViaSOCKS5,
+		rules:            rules.NewPipeline(externalRules),
 	}
 }
 
@@ -343,10 +356,15 @@ func (w *IMAPWatcher) processMessage(c *imapclient.Client, buf *imapclient.Fetch
 		return
 	}
 
-	// 2. Whitelist: skip if sender not in allowed list.
-	if !w.isWhitelisted(sender) {
-		log.Info("imap: sender not whitelisted, ignoring", "sender", sender)
-		w.saveIgnored(messageID, sender, subject, "not whitelisted")
+	// 2. External rules: evaluate operator-configurable policy.
+	ruleResult := w.rules.Evaluate(rules.EmailContext{
+		Sender:    sender,
+		Subject:   subject,
+		MessageID: messageID,
+	})
+	if !ruleResult.Accepted {
+		log.Info("imap: rejected by external rules", "sender", sender, "reason", ruleResult.Reason)
+		w.saveIgnored(messageID, sender, subject, ruleResult.Reason)
 		w.markSeen(c, buf.UID)
 		return
 	}
@@ -404,13 +422,14 @@ func (w *IMAPWatcher) processMessage(c *imapclient.Client, buf *imapclient.Fetch
 	// 5. Save task with status RECEIVED.
 	taskUUID := uuid.New().String()
 	task := &database.Task{
-		TaskUUID:  taskUUID,
-		ThreadID:  threadID,
-		MessageID: messageID,
-		Sender:    sender,
-		Subject:   subject,
-		BodyPlain: bodyPlain,
-		Status:    database.StatusReceived,
+		TaskUUID:        taskUUID,
+		ThreadID:        threadID,
+		MessageID:       messageID,
+		Sender:          sender,
+		Subject:         subject,
+		BodyPlain:       bodyPlain,
+		DispatchContext: marshalDispatchContext(ruleResult.Metadata),
+		Status:          database.StatusReceived,
 	}
 
 	taskLog := logging.TaskLogger(taskUUID, threadID, messageID)
@@ -453,19 +472,13 @@ func (w *IMAPWatcher) saveIgnored(messageID, sender, subject, reason string) {
 	}
 }
 
-// isWhitelisted checks if the sender is in the allowed list.
-// Empty whitelist means all senders are allowed.
-func (w *IMAPWatcher) isWhitelisted(sender string) bool {
-	if len(w.cfg.WhitelistEmails) == 0 {
-		return true
+// marshalDispatchContext serializes rule metadata to JSON.
+func marshalDispatchContext(metadata map[string]string) string {
+	if len(metadata) == 0 {
+		return ""
 	}
-	lower := strings.ToLower(sender)
-	for _, email := range w.cfg.WhitelistEmails {
-		if strings.ToLower(email) == lower {
-			return true
-		}
-	}
-	return false
+	data, _ := json.Marshal(metadata)
+	return string(data)
 }
 
 // markSeen flags a message as \Seen in IMAP.