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/utils/optionals.go

@@ -21,7 +21,6 @@ func CreateOptionalBool(input bool) *bool {
 	return &input
 }
 
-// OptionalString converts a non-nil *string to the respective string or returns "".
 func OptionalString(input *string) string {
 	if input == nil {
 		return ""
@@ -30,7 +29,6 @@ func OptionalString(input *string) string {
 	return *input
 }
 
-// OptionalInt converts a non-nil *int to the respective int, otherwise returns 0.
 func OptionalInt(input *int) int {
 	if input == nil {
 		return 0
@@ -39,8 +37,7 @@ func OptionalInt(input *int) int {
 	return *input
 }
 
-// CreateOptionalInt when given a zero value int (0), it returns a nil *int.
-// Otherwise, it gives a proper *int with valid value.
+// Zero values become nil; the inverse of OptionalInt.
 func CreateOptionalInt(input int) *int {
 	if input == 0 {
 		return nil
@@ -49,8 +46,7 @@ func CreateOptionalInt(input int) *int {
 	return &input
 }
 
-// CreateOptionalString when given an empty string, it returns a nil *string.
-// Otherwise, it gives a proper *string with valid value.
+// Empty string becomes nil; the inverse of OptionalString.
 func CreateOptionalString(input string) *string {
 	if input == "" {
 		return nil
@@ -59,8 +55,7 @@ func CreateOptionalString(input string) *string {
 	return &input
 }
 
-// GetNumberFromString converts a string to a number.
-// Returns error if the query is not a number.
+// Returns an error if input contains non-digit characters or parses to <= 0.
 func GetNumberFromString(input string) (int, error) {
 	for _, c := range input {
 		if c < '0' || c > '9' {
@@ -80,7 +75,6 @@ type Number interface {
 	int | int8 | int16 | int32 | int64 | uint | uint8 | uint16 | uint32 | uint64 | float32 | float64
 }
 
-// OptionalNumber converts a non-nil *NUMBER to the respective number value or returns 0.
 func OptionalNumber[T Number](input *T) T {
 	if input == nil {
 		return 0
@@ -89,7 +83,7 @@ func OptionalNumber[T Number](input *T) T {
 	return *input
 }
 
-// CreateOptionalNumber when given an zero value NUMBER (0), it returns a nil *NUMBER, otherwise, it gives a proper *NUMBER with valid value.
+// Zero values become nil; the inverse of OptionalNumber.
 func CreateOptionalNumber[T Number](input T) *T {
 	if input == 0 {
 		return nil