feat: add ability to run multiple agents via tabbed views (#47)

### Explanation

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### Issue

Closes #30 Closes #41

### Attestations

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- [ ] I have read and agree to the [Community Guidelines](https://docs.nhcarrigan.com/community/guide/).
- [ ] My contribution complies with the [Contributor Covenant](https://docs.nhcarrigan.com/dev/covenant/).

### Dependencies

- [ ] I have pinned the dependencies to a specific patch version.

### Style

- [ ] I have run the linter and resolved any errors.
- [ ] My pull request uses an appropriate title, matching the conventional commit standards.
- [ ] My scope of feat/fix/chore/etc. correctly matches the nature of changes in my pull request.

### Tests

- [ ] My contribution adds new code, and I have added tests to cover it.
- [ ] My contribution modifies existing code, and I have updated the tests to reflect these changes.
- [ ] All new and existing tests pass locally with my changes.
- [ ] Code coverage remains at or above the configured threshold.

### Documentation

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### Versioning

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Reviewed-on: #47
Co-authored-by: Naomi Carrigan <commits@nhcarrigan.com>
Co-committed-by: Naomi Carrigan <commits@nhcarrigan.com>

src-tauri/src/bridge_manager.rs

@@ -0,0 +1,135 @@
+use parking_lot::Mutex;
+use std::collections::HashMap;
+use std::sync::Arc;
+use tauri::AppHandle;
+
+use crate::config::ClaudeStartOptions;
+use crate::stats::UsageStats;
+use crate::wsl_bridge::WslBridge;
+
+pub struct BridgeManager {
+    bridges: HashMap<String, WslBridge>,
+    app_handle: Option<AppHandle>,
+}
+
+impl BridgeManager {
+    pub fn new() -> Self {
+        BridgeManager {
+            bridges: HashMap::new(),
+            app_handle: None,
+        }
+    }
+
+    pub fn set_app_handle(&mut self, app: AppHandle) {
+        self.app_handle = Some(app);
+    }
+
+    pub fn start_claude(
+        &mut self,
+        conversation_id: &str,
+        options: ClaudeStartOptions,
+    ) -> Result<(), String> {
+        // Check if a bridge already exists for this conversation
+        if self.bridges.get(conversation_id).map(|b| b.is_running()).unwrap_or(false) {
+            return Err("Claude is already running for this conversation".to_string());
+        }
+
+        let app = self.app_handle.as_ref()
+            .ok_or_else(|| "App handle not set".to_string())?
+            .clone();
+
+        // Create a new bridge for this conversation
+        let mut bridge = WslBridge::new_with_conversation_id(conversation_id.to_string());
+
+        // Start the Claude process
+        bridge.start(app, options)?;
+
+        // Store the bridge
+        self.bridges.insert(conversation_id.to_string(), bridge);
+
+        Ok(())
+    }
+
+    pub fn stop_claude(&mut self, conversation_id: &str) -> Result<(), String> {
+        if let Some(bridge) = self.bridges.get_mut(conversation_id) {
+            let app = self.app_handle.as_ref()
+                .ok_or_else(|| "App handle not set".to_string())?;
+            bridge.stop(app);
+            Ok(())
+        } else {
+            Err("No Claude instance found for this conversation".to_string())
+        }
+    }
+
+    pub fn interrupt_claude(&mut self, conversation_id: &str) -> Result<(), String> {
+        if let Some(bridge) = self.bridges.get_mut(conversation_id) {
+            let app = self.app_handle.as_ref()
+                .ok_or_else(|| "App handle not set".to_string())?;
+            bridge.interrupt(app)
+        } else {
+            Err("No Claude instance found for this conversation".to_string())
+        }
+    }
+
+    pub fn send_prompt(&mut self, conversation_id: &str, message: String) -> Result<(), String> {
+        if let Some(bridge) = self.bridges.get_mut(conversation_id) {
+            bridge.send_message(&message)
+        } else {
+            Err("No Claude instance found for this conversation".to_string())
+        }
+    }
+
+    pub fn is_claude_running(&self, conversation_id: &str) -> bool {
+        self.bridges.get(conversation_id)
+            .map(|b| b.is_running())
+            .unwrap_or(false)
+    }
+
+    pub fn get_working_directory(&self, conversation_id: &str) -> Result<String, String> {
+        self.bridges.get(conversation_id)
+            .map(|b| b.get_working_directory().to_string())
+            .ok_or_else(|| "No Claude instance found for this conversation".to_string())
+    }
+
+    pub fn get_usage_stats(&self, conversation_id: &str) -> Result<UsageStats, String> {
+        self.bridges.get(conversation_id)
+            .map(|b| b.get_stats())
+            .ok_or_else(|| "No Claude instance found for this conversation".to_string())
+    }
+
+    #[allow(dead_code)]
+    pub fn cleanup_stopped_bridges(&mut self) {
+        // Remove bridges that are no longer running
+        self.bridges.retain(|_, bridge| bridge.is_running());
+    }
+
+    #[allow(dead_code)]
+    pub fn stop_all(&mut self) {
+        if let Some(app) = &self.app_handle {
+            for (_, bridge) in self.bridges.iter_mut() {
+                bridge.stop(app);
+            }
+        }
+        self.bridges.clear();
+    }
+
+    #[allow(dead_code)]
+    pub fn get_active_conversations(&self) -> Vec<String> {
+        self.bridges.keys()
+            .filter(|id| self.bridges.get(*id).map(|b| b.is_running()).unwrap_or(false))
+            .cloned()
+            .collect()
+    }
+}
+
+impl Default for BridgeManager {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+pub type SharedBridgeManager = Arc<Mutex<BridgeManager>>;
+
+pub fn create_shared_bridge_manager() -> SharedBridgeManager {
+    Arc::new(Mutex::new(BridgeManager::new()))
+}