[fix](trx-rs): use per-message rig_id for map marker tagging

The map module was tagging all decode markers (APRS, AIS, VDES,
FT8/FT4/FT2/WSPR locators) with the global rig picker's active rig
instead of the actual source rig. This made the map's own rig filter
dropdown ineffective in multi-rig setups.

- Add rig_id field to all decode message structs (AisMessage,
  VdesMessage, AprsPacket, CwEvent, Ft8Message, WsprMessage)
- Set rig_id on messages in audio_client before broadcasting, using
  the actual rig connection identifier
- Update history collector to prefer message rig_id over the global
  active rig fallback
- Pass rig_id through plugin normalize functions (AIS, APRS, VDES,
  HF-APRS) so it reaches the map add functions
- Update all map marker functions (aprsMapAddStation, aisMapAddVessel,
  vdesMapAddPoint, mapAddLocator) to use the message's rig_id with
  fallback to the global picker for backward compatibility

https://claude.ai/code/session_015gC7axHk2jmp7HbFPdbivN
Signed-off-by: Claude <noreply@anthropic.com>

src/trx-core/src/decode.rs

@@ -30,8 +30,36 @@ pub enum DecodedMessage {
     Wspr(WsprMessage),
 }
 
+impl DecodedMessage {
+    /// Attach a rig identifier to the inner message variant.
+    pub fn set_rig_id(&mut self, id: String) {
+        match self {
+            Self::Ais(m) => m.rig_id = Some(id),
+            Self::Vdes(m) => m.rig_id = Some(id),
+            Self::Aprs(m) | Self::HfAprs(m) => m.rig_id = Some(id),
+            Self::Cw(m) => m.rig_id = Some(id),
+            Self::Ft8(m) | Self::Ft4(m) | Self::Ft2(m) => m.rig_id = Some(id),
+            Self::Wspr(m) => m.rig_id = Some(id),
+        }
+    }
+
+    /// Return the rig identifier from the inner message variant, if set.
+    pub fn rig_id(&self) -> Option<&str> {
+        match self {
+            Self::Ais(m) => m.rig_id.as_deref(),
+            Self::Vdes(m) => m.rig_id.as_deref(),
+            Self::Aprs(m) | Self::HfAprs(m) => m.rig_id.as_deref(),
+            Self::Cw(m) => m.rig_id.as_deref(),
+            Self::Ft8(m) | Self::Ft4(m) | Self::Ft2(m) => m.rig_id.as_deref(),
+            Self::Wspr(m) => m.rig_id.as_deref(),
+        }
+    }
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct AisMessage {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub rig_id: Option<String>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub ts_ms: Option<i64>,
     pub channel: String,
@@ -63,6 +91,8 @@ pub struct AisMessage {
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct VdesMessage {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub rig_id: Option<String>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub ts_ms: Option<i64>,
     pub channel: String,
@@ -122,6 +152,8 @@ pub struct VdesMessage {
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct AprsPacket {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub rig_id: Option<String>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub ts_ms: Option<i64>,
     pub src_call: String,
@@ -143,6 +175,8 @@ pub struct AprsPacket {
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct CwEvent {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub rig_id: Option<String>,
     /// Decoded text fragment (one or more characters)
     pub text: String,
     /// Current detected WPM
@@ -155,6 +189,8 @@ pub struct CwEvent {
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct Ft8Message {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub rig_id: Option<String>,
     /// UTC timestamp (milliseconds since epoch)
     pub ts_ms: i64,
     /// Approximate SNR (dB)
@@ -169,6 +205,8 @@ pub struct Ft8Message {
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct WsprMessage {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub rig_id: Option<String>,
     /// UTC timestamp (milliseconds since epoch)
     pub ts_ms: i64,
     /// Approximate SNR (dB)