Add startup persistence for support sessions

- Added startup.rs module for Windows registry operations
- Agent adds itself to HKCU\...\Run on session start
- Agent removes itself from startup on session end
- Works with user-level registry (no admin required)
- Added Win32_System_Registry feature to windows crate

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

agent/src/startup.rs

@@ -0,0 +1,146 @@
+//! Startup persistence for the agent
+//!
+//! Handles adding/removing the agent from Windows startup.
+
+use anyhow::Result;
+use tracing::{info, warn, error};
+
+#[cfg(windows)]
+use windows::Win32::System::Registry::{
+    RegOpenKeyExW, RegSetValueExW, RegDeleteValueW, RegCloseKey,
+    HKEY_CURRENT_USER, KEY_WRITE, REG_SZ,
+};
+#[cfg(windows)]
+use windows::core::PCWSTR;
+
+const STARTUP_KEY: &str = r"Software\Microsoft\Windows\CurrentVersion\Run";
+const STARTUP_VALUE_NAME: &str = "GuruConnect";
+
+/// Add the current executable to Windows startup
+#[cfg(windows)]
+pub fn add_to_startup() -> Result<()> {
+    use std::ffi::OsStr;
+    use std::os::windows::ffi::OsStrExt;
+
+    // Get the path to the current executable
+    let exe_path = std::env::current_exe()?;
+    let exe_path_str = exe_path.to_string_lossy();
+
+    info!("Adding to startup: {}", exe_path_str);
+
+    // Convert strings to wide strings
+    let key_path: Vec<u16> = OsStr::new(STARTUP_KEY)
+        .encode_wide()
+        .chain(std::iter::once(0))
+        .collect();
+    let value_name: Vec<u16> = OsStr::new(STARTUP_VALUE_NAME)
+        .encode_wide()
+        .chain(std::iter::once(0))
+        .collect();
+    let value_data: Vec<u16> = OsStr::new(&*exe_path_str)
+        .encode_wide()
+        .chain(std::iter::once(0))
+        .collect();
+
+    unsafe {
+        let mut hkey = windows::Win32::Foundation::HANDLE::default();
+
+        // Open the Run key
+        let result = RegOpenKeyExW(
+            HKEY_CURRENT_USER,
+            PCWSTR(key_path.as_ptr()),
+            0,
+            KEY_WRITE,
+            &mut hkey as *mut _ as *mut _,
+        );
+
+        if result.is_err() {
+            anyhow::bail!("Failed to open registry key: {:?}", result);
+        }
+
+        let hkey_raw = std::mem::transmute::<_, windows::Win32::System::Registry::HKEY>(hkey);
+
+        // Set the value
+        let data_bytes = std::slice::from_raw_parts(
+            value_data.as_ptr() as *const u8,
+            value_data.len() * 2,
+        );
+
+        let set_result = RegSetValueExW(
+            hkey_raw,
+            PCWSTR(value_name.as_ptr()),
+            0,
+            REG_SZ,
+            Some(data_bytes),
+        );
+
+        let _ = RegCloseKey(hkey_raw);
+
+        if set_result.is_err() {
+            anyhow::bail!("Failed to set registry value: {:?}", set_result);
+        }
+    }
+
+    info!("Successfully added to startup");
+    Ok(())
+}
+
+/// Remove the agent from Windows startup
+#[cfg(windows)]
+pub fn remove_from_startup() -> Result<()> {
+    use std::ffi::OsStr;
+    use std::os::windows::ffi::OsStrExt;
+
+    info!("Removing from startup");
+
+    let key_path: Vec<u16> = OsStr::new(STARTUP_KEY)
+        .encode_wide()
+        .chain(std::iter::once(0))
+        .collect();
+    let value_name: Vec<u16> = OsStr::new(STARTUP_VALUE_NAME)
+        .encode_wide()
+        .chain(std::iter::once(0))
+        .collect();
+
+    unsafe {
+        let mut hkey = windows::Win32::Foundation::HANDLE::default();
+
+        let result = RegOpenKeyExW(
+            HKEY_CURRENT_USER,
+            PCWSTR(key_path.as_ptr()),
+            0,
+            KEY_WRITE,
+            &mut hkey as *mut _ as *mut _,
+        );
+
+        if result.is_err() {
+            warn!("Failed to open registry key for removal: {:?}", result);
+            return Ok(()); // Not an error if key doesn't exist
+        }
+
+        let hkey_raw = std::mem::transmute::<_, windows::Win32::System::Registry::HKEY>(hkey);
+
+        let delete_result = RegDeleteValueW(hkey_raw, PCWSTR(value_name.as_ptr()));
+
+        let _ = RegCloseKey(hkey_raw);
+
+        if delete_result.is_err() {
+            warn!("Registry value may not exist: {:?}", delete_result);
+        } else {
+            info!("Successfully removed from startup");
+        }
+    }
+
+    Ok(())
+}
+
+#[cfg(not(windows))]
+pub fn add_to_startup() -> Result<()> {
+    warn!("Startup persistence not implemented for this platform");
+    Ok(())
+}
+
+#[cfg(not(windows))]
+pub fn remove_from_startup() -> Result<()> {
+    Ok(())
+}