Mobile notifications for iOS (#210)

* mobile: wire notification registration and listener

* implement backend components for push notifications

* refactor: agentic comment cleanup

* docs: use proper module name for particle processor

* set required env variables for push notifications

* bump version

* fix: always upsert push token on mobile start

* Revert "fix: always upsert push token on mobile start"

This reverts commit 90ff18a788.

* send push notifications regardless of online status

go/internal/human/pushnotify/service.go

@@ -0,0 +1,66 @@
+package pushnotify
+
+import (
+	"context"
+
+	"github.com/jackc/pgx/v5/pgxpool"
+)
+
+// Service stores per-device Expo push tokens and exposes the operations
+// needed by both the HTTP handlers and the worker-side notifier.
+type Service interface {
+	// Register returns ErrInvalidToken / ErrInvalidPlatform on bad input.
+	Register(ctx context.Context, humanID string, in RegisterInput) error
+	// Unregister is scoped to humanID so a user can't delete another user's
+	// token. Returns ErrNotFound if the token isn't owned by humanID.
+	Unregister(ctx context.Context, humanID, token string) error
+	// ListForHumans returns an empty slice when nothing matches.
+	ListForHumans(ctx context.Context, humanIDs []string) ([]*PushToken, error)
+	// DeleteByToken removes a token regardless of owner — used to prune after
+	// Expo reports DeviceNotRegistered.
+	DeleteByToken(ctx context.Context, token string) error
+}
+
+type RegisterInput struct {
+	Token      string
+	Platform   Platform
+	AppVersion string
+}
+
+type serviceImpl struct {
+	repo repository
+}
+
+func NewService(pool *pgxpool.Pool) Service {
+	return &serviceImpl{repo: newRepository(pool)}
+}
+
+func (s *serviceImpl) Register(ctx context.Context, humanID string, in RegisterInput) error {
+	if !in.Platform.Valid() {
+		return ErrInvalidPlatform
+	}
+	if !IsValidExpoToken(in.Token) {
+		return ErrInvalidToken
+	}
+	return s.repo.upsert(ctx, &PushToken{
+		Token:      in.Token,
+		HumanID:    humanID,
+		Platform:   in.Platform,
+		AppVersion: in.AppVersion,
+	})
+}
+
+func (s *serviceImpl) Unregister(ctx context.Context, humanID, token string) error {
+	if token == "" {
+		return ErrInvalidToken
+	}
+	return s.repo.deleteForHuman(ctx, humanID, token)
+}
+
+func (s *serviceImpl) ListForHumans(ctx context.Context, humanIDs []string) ([]*PushToken, error) {
+	return s.repo.listForHumans(ctx, humanIDs)
+}
+
+func (s *serviceImpl) DeleteByToken(ctx context.Context, token string) error {
+	return s.repo.deleteByToken(ctx, token)
+}