Add windows support in strider (#4854)

* Add Windows path support to strider plugin

Strider is a WASM plugin where std::path::PathBuf uses Unix semantics,
so Windows backslash paths break parent(), join(), strip_prefix(), etc.

Fix by normalizing all incoming paths to forward slashes at plugin
boundaries and converting back to native backslashes for display. A new
platform.rs module detects the host OS at runtime from the initial_cwd
format and centralizes all platform-aware logic.

Also fix scan_host_folder on the server side: canonicalize
plugin_host_folder so the starts_with security check works on Windows,
where canonicalize() adds the \?\ prefix.

* Add virtual root view for drive and WSL navigation in strider

On Windows, navigating up from a drive root (e.g. C:\) now shows a
"Computer" view listing all available drives and WSL distributions.
Drives are enumerated via GetLogicalDriveStringsW and WSL distros
via `wsl -l -q` (since read_dir on \wsl.localhost fails with OS
error 64/67). Drive letters appear before WSL entries, which are
displayed as "Ubuntu-24.04 (WSL)" etc. On non-Windows platforms,
behavior is unchanged.

* Rename ListHostEntries to ListWindowsVolumes and gate behind FullHdAccess

The old name was misleading — on Unix it just returned `/`, which isn't
"listing host entries." Rename to ListWindowsVolumes to make the
Windows-specific intent explicit, gate behind FullHdAccess permission,
and replace the Unix implementation with a log::error since the command
is not meaningful on non-Windows platforms.

* Replace direct array indexing with .get() in strider platform detection

Use safe accessors and matches! macro instead of direct byte indexing
for bounds-checked access patterns.

---------

Co-authored-by: divens <divens.dev@gmail.com>

2 files changed, 9 insertions, 0 deletions

diff --git a/zellij-utils/src/plugin_api/plugin_command.proto b/zellij-utils/src/plugin_api/plugin_command.proto
index f00ffdd1..63baa443 100644
--- a/zellij-utils/src/plugin_api/plugin_command.proto
+++ b/zellij-utils/src/plugin_api/plugin_command.proto
@@ -202,6 +202,7 @@ enum CommandName {
   SetPaneRegexHighlights = 207;
   ClearPaneHighlights = 208;
   OpenPluginPaneFloating = 209;
+  ListWindowsVolumes = 210;
 }
 
 message PluginCommand {
diff --git a/zellij-utils/src/plugin_api/plugin_command.rs b/zellij-utils/src/plugin_api/plugin_command.rs
index fc55dd91..a457f720 100644
--- a/zellij-utils/src/plugin_api/plugin_command.rs
+++ b/zellij-utils/src/plugin_api/plugin_command.rs
@@ -1296,6 +1296,10 @@ impl TryFrom<ProtobufPluginCommand> for PluginCommand {
                 Some(_) => Err("WatchFilesystem should have no payload, found a payload"),
                 None => Ok(PluginCommand::WatchFilesystem),
             },
+            Some(CommandName::ListWindowsVolumes) => match protobuf_plugin_command.payload {
+                Some(_) => Err("ListWindowsVolumes should have no payload"),
+                None => Ok(PluginCommand::ListWindowsVolumes),
+            },
             Some(CommandName::DumpSessionLayout) => match protobuf_plugin_command.payload {
                 Some(Payload::DumpSessionLayoutPayload(payload)) => {
                     Ok(PluginCommand::DumpSessionLayout {
@@ -3137,6 +3141,10 @@ impl TryFrom<PluginCommand> for ProtobufPluginCommand {
                 name: CommandName::WatchFilesystem as i32,
                 payload: None,
             }),
+            PluginCommand::ListWindowsVolumes => Ok(ProtobufPluginCommand {
+                name: CommandName::ListWindowsVolumes as i32,
+                payload: None,
+            }),
             PluginCommand::DumpSessionLayout { tab_index } => Ok(ProtobufPluginCommand {
                 name: CommandName::DumpSessionLayout as i32,
                 payload: tab_index.map(|idx| {