refactor: eradicate deprecated tools (sticky_notes, pinned_files, context_workspaces, pr_checklist, preferences) and dead code

nvim-core/src/lib.rs

@@ -167,6 +167,43 @@ async fn get_socket_path() -> Result<String, String> {
     }
     Err("Could not find Neovim socket".to_string())
 }
+
+#[cfg(windows)]
+async fn read_active_socket_file() -> Result<String, String> {
+    let profile = dirs::home_dir()
+        .map(|p| p.to_string_lossy().to_string())
+        .or_else(|| std::env::var("USERPROFILE").ok())
+        .ok_or_else(|| "Could not determine user home directory".to_string())?;
+    let path = format!("{profile}\\.gemini\\active_nvim.txt");
+    if let Ok(content) = tokio::fs::read_to_string(&path).await {
+        let p = content.trim().to_string();
+        if !p.is_empty() {
+            let candidate = if p.starts_with(r"\\.\pipe\") {
+                p
+            } else if p.starts_with("nvim.") {
+                format!(r"\\.\pipe\{p}")
+            } else {
+                p
+            };
+            return Ok(candidate);
+        }
+    }
+    Err("Missing active_nvim.txt".to_string())
+}
+
+#[cfg(unix)]
+async fn read_active_socket_file() -> Result<String, String> {
+    if let Some(home) = dirs::home_dir() {
+        let path = home.join(".gemini/active_nvim.txt");
+        if let Ok(content) = tokio::fs::read_to_string(&path).await {
+            let p = content.trim().to_string();
+            if !p.is_empty() {
+                return Ok(p);
+            }
+        }
+    }
+    Err("Missing active_nvim.txt".to_string())
+}
 use std::sync::Arc;
 use std::sync::LazyLock;
 use tokio::sync::{mpsc, oneshot};
@@ -222,6 +259,24 @@ fn handle_nvim_notification(params: &[rmpv::Value]) {
 }
 
 async fn get_nvim_connection() -> Result<mpsc::Sender<NvimRequest>, String> {
+    // Fast path: If NVIM_CONN is already active and healthy, check if active_nvim.txt matches
+    // without spawning any external nvim.exe child process!
+    {
+        let conn_lock = NVIM_CONN.lock().await;
+        if let Some(sender) = conn_lock.as_ref() {
+            if !sender.is_closed() {
+                let active_lock = ACTIVE_SOCKET.lock().await;
+                if let Some(ref current_socket) = *active_lock {
+                    if let Ok(target) = read_active_socket_file().await {
+                        if !target.is_empty() && &target == current_socket {
+                            return Ok(sender.clone());
+                        }
+                    }
+                }
+            }
+        }
+    }
+
     let interactive_socket = get_socket_path().await.ok();
     let mut should_kill_headless = false;