mmrs: sms support

[cachebag]

add sms send/receive support via Modem.Messaging and Sms interfaces.

scope

• list sms messages
• read sms content
• send sms
• delete sms
• incoming sms notification stream

api sketch

pub struct Sms {
    pub path: String,
    pub number: String,
    pub text: String,
    pub timestamp: Option<String>,
    pub state: SmsState,
}

pub enum SmsState {
    Unknown,
    Stored,
    Receiving,
    Received,
    Sending,
    Sent,
}

pub async fn list_sms(&self) -> Result<Vec<Sms>>;
pub async fn send_sms(&self, number: &str, text: &str) -> Result<()>;
pub async fn delete_sms(&self, path: &str) -> Result<()>;
pub async fn monitor_sms(&self) -> Result<impl Stream<Item = Sms> + Send>;

interfaces

• Modem.Messaging.List() → sms paths
• Modem.Messaging.Create(properties) → create sms object
• Sms.Send() — send the sms
• Sms.Number, Sms.Text, Sms.State properties

priority

marking low-priority — core modem/bearer/sim functionality comes first. sms can be a follow-up release.