feat(ingestion): wire watcher into server startup + fix Procfile env vars

- Start background watcher on startup when INGEST_WATCH_INTERVAL > 0
- Procfile: add INGEST_WATCH_INTERVAL=30 and INGEST_SVC_URL for supervisor

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Procfile

@@ -1,2 +1,2 @@
-ingestion: cd ingestion && INGEST_BRAIN_DIR=../brain INGEST_PORT=3300 go run ./cmd/server/
-supervisor: SUPERVISOR_CONFIG_DIR=./config/supervisor SUPERVISOR_MODELS_FILE=./config/models.yaml SUPERVISOR_SESSIONS_DIR=./brain/sessions INGEST_BASE_URL=http://localhost:3300 go run ./cmd/supervisor/
+ingestion: cd ingestion && INGEST_BRAIN_DIR=../brain INGEST_PORT=3300 INGEST_WATCH_INTERVAL=30 go run ./cmd/server/
+supervisor: SUPERVISOR_CONFIG_DIR=./config/supervisor SUPERVISOR_MODELS_FILE=./config/models.yaml SUPERVISOR_SESSIONS_DIR=./brain/sessions INGEST_BASE_URL=http://localhost:3300 INGEST_SVC_URL=http://localhost:3300 go run ./cmd/supervisor/

ingestion/cmd/server/main.go

@@ -2,6 +2,7 @@
 package main
 
 import (
+	"context"
 	"fmt"
 	"log/slog"
 	"net/http"
@@ -12,6 +13,7 @@ import (
 	"github.com/mathiasbq/hyperguild/ingestion/internal/api"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/llm"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/pipeline"
+	"github.com/mathiasbq/hyperguild/ingestion/internal/watcher"
 )
 
 func envOr(key, fallback string) string {
@@ -52,8 +54,14 @@ func main() {
 
 	h := api.NewHandler(brainDir, logger, pipelineCfg)
 
-	// TODO(task11): start watcher when INGEST_WATCH_INTERVAL > 0
-	_ = watchInterval
+	ctx := context.Background()
+	if watchInterval > 0 {
+		watcher.Start(ctx, watcher.Config{
+			BrainDir: brainDir,
+			Interval: time.Duration(watchInterval) * time.Second,
+			Pipeline: pipelineCfg,
+		})
+	}
 
 	mux := http.NewServeMux()
 	mux.HandleFunc("POST /query", h.Query)
@@ -64,7 +72,7 @@ func main() {
 	addr := ":" + port
 	watchIntervalLog := "disabled"
 	if watchInterval > 0 {
-		watchIntervalLog = fmt.Sprintf("%ds (pending task11 wiring)", watchInterval)
+		watchIntervalLog = fmt.Sprintf("%ds", watchInterval)
 	}
 	logger.Info("ingestion server starting",
 		"addr", addr,