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/pusher/conn.go

@@ -11,13 +11,12 @@ import (
 
 const sendBufferSize = 256
 
-// Conn wraps a WebSocket connection with identity and a send buffer.
 type Conn struct {
 	id      string
 	humanID string
 	ws      *websocket.Conn
 	send    chan []byte
-	once    sync.Once // ensures close logic runs once
+	once    sync.Once // guards Close
 }
 
 func newConn(id, humanID string, ws *websocket.Conn) *Conn {
@@ -29,8 +28,8 @@ func newConn(id, humanID string, ws *websocket.Conn) *Conn {
 	}
 }
 
-// ReadPump reads messages from the WebSocket and forwards them to the hub.
-// It blocks until the connection is closed or the context is cancelled.
+// ReadPump forwards inbound frames to the hub; blocks until the connection
+// closes or ctx is cancelled.
 func (c *Conn) ReadPump(ctx context.Context, hub *Hub) {
 	defer hub.disconnect(c)
 
@@ -45,7 +44,6 @@ func (c *Conn) ReadPump(ctx context.Context, hub *Hub) {
 			return
 		}
 
-		// Respond to keep-alive pings
 		if string(data) == "ping" {
 			if err := c.ws.Write(ctx, websocket.MessageText, []byte("pong")); err != nil {
 				slog.Warn("websocket pong write error", "connId", c.id, "error", err)
@@ -84,7 +82,6 @@ func (c *Conn) ReadPump(ctx context.Context, hub *Hub) {
 	}
 }
 
-// WritePump drains the send buffer and writes messages to the WebSocket.
 func (c *Conn) WritePump(ctx context.Context) {
 	for {
 		select {
@@ -102,8 +99,7 @@ func (c *Conn) WritePump(ctx context.Context) {
 	}
 }
 
-// Send enqueues a ServerMessage to be written to the WebSocket.
-// If the send buffer is full, the connection is closed (slow client).
+// A full send buffer closes the connection (slow client policy).
 func (c *Conn) Send(msg ServerMessage) {
 	data, err := json.Marshal(msg)
 	if err != nil {
@@ -119,7 +115,6 @@ func (c *Conn) Send(msg ServerMessage) {
 	}
 }
 
-// Close closes the WebSocket connection and the send channel.
 func (c *Conn) Close() {
 	c.once.Do(func() {
 		c.ws.Close(websocket.StatusNormalClosure, "closing")