arch: split ConfigRepository, extract polling, consolidate conversions, decouple protocol

- Value↔JSON: From impls on domain Value behind `json` feature, delete 4 duplicate converters
- ConfigRepository split into ConfigRepository (12), UserRepository (3), WidgetStateCache (2)
- polling orchestration moved from bootstrap to application::polling_service
- WidgetRenderer in client-domain owns scroll/cache, both clients use it
- network loop consolidated into client-application::run_connection_loop
- protocol crate drops domain dep, Wire↔Domain conversions move to adapters

crates/adapters/config-sqlite/src/repository/mod.rs

@@ -10,7 +10,7 @@ use crate::SqliteConfigStore;
 use crate::error::SqliteConfigError;
 use domain::{
     ConfigRepository, DataSource, DataSourceId, Layout, LayoutPreset, LayoutPresetId, ThemeConfig,
-    User, WidgetConfig, WidgetId, WidgetState,
+    User, UserRepository, WidgetConfig, WidgetId, WidgetState, WidgetStateCache,
 };
 
 impl ConfigRepository for SqliteConfigStore {
@@ -79,6 +79,10 @@ impl ConfigRepository for SqliteConfigStore {
     async fn save_theme(&self, theme: &ThemeConfig) -> Result<(), Self::Error> {
         self.save_theme_impl(theme).await
     }
+}
+
+impl UserRepository for SqliteConfigStore {
+    type Error = SqliteConfigError;
 
     async fn get_user_by_username(&self, username: &str) -> Result<Option<User>, Self::Error> {
         self.get_user_by_username_impl(username).await
@@ -91,6 +95,10 @@ impl ConfigRepository for SqliteConfigStore {
     async fn count_users(&self) -> Result<u32, Self::Error> {
         self.count_users_impl().await
     }
+}
+
+impl WidgetStateCache for SqliteConfigStore {
+    type Error = SqliteConfigError;
 
     async fn save_widget_states(
         &self,

crates/adapters/config-sqlite/src/repository/widget_state_cache.rs

@@ -44,56 +44,17 @@ impl SqliteConfigStore {
     }
 }
 
-fn domain_value_to_json(v: &Value) -> serde_json::Value {
-    match v {
-        Value::Null => serde_json::Value::Null,
-        Value::Bool(b) => serde_json::Value::Bool(*b),
-        Value::Number(n) => serde_json::json!(n),
-        Value::String(s) => serde_json::Value::String(s.clone()),
-        Value::Array(arr) => {
-            serde_json::Value::Array(arr.iter().map(domain_value_to_json).collect())
-        }
-        Value::Object(map) => {
-            let obj: serde_json::Map<String, serde_json::Value> = map
-                .iter()
-                .map(|(k, v)| (k.clone(), domain_value_to_json(v)))
-                .collect();
-            serde_json::Value::Object(obj)
-        }
-    }
-}
-
-fn json_value_to_domain(v: &serde_json::Value) -> Value {
-    match v {
-        serde_json::Value::Null => Value::Null,
-        serde_json::Value::Bool(b) => Value::Bool(*b),
-        serde_json::Value::Number(n) => Value::Number(n.as_f64().unwrap_or(0.0)),
-        serde_json::Value::String(s) => Value::String(s.clone()),
-        serde_json::Value::Array(arr) => {
-            Value::Array(arr.iter().map(json_value_to_domain).collect())
-        }
-        serde_json::Value::Object(map) => Value::Object(
-            map.iter()
-                .map(|(k, v)| (k.clone(), json_value_to_domain(v)))
-                .collect(),
-        ),
-    }
-}
-
 fn domain_state_to_json(state: &WidgetState) -> Result<String, serde_json::Error> {
     let data: serde_json::Map<String, serde_json::Value> = state
         .data
         .iter()
-        .map(|(k, v)| (k.clone(), domain_value_to_json(v)))
+        .map(|(k, v)| (k.clone(), v.into()))
         .collect();
     serde_json::to_string(&data)
 }
 
 fn json_to_domain_state(json: &str) -> Result<WidgetState, serde_json::Error> {
     let map: serde_json::Map<String, serde_json::Value> = serde_json::from_str(json)?;
-    let data: BTreeMap<String, Value> = map
-        .iter()
-        .map(|(k, v)| (k.clone(), json_value_to_domain(v)))
-        .collect();
+    let data: BTreeMap<String, Value> = map.into_iter().map(|(k, v)| (k, v.into())).collect();
     Ok(WidgetState { data, error: None })
 }