Read MIM_SOCKET in mimctl mode

src/main.zig

@@ -11,7 +11,7 @@ const help_text =
     \\Usage:
     \\  mim [--help]
     \\  mim [--version]
-    \\  mim --mimctl <socket> <request...>
+    \\  mim --mimctl <socket|-> <request...>
     \\
     \\This early build exposes the canonical smoke path and a minimal local
     \\session-control client for trusted tools.
@@ -62,7 +62,16 @@ pub fn main(init: std.process.Init) !u8 {
                 try stderr.writeStreamingAll(init.io, "mim: --mimctl requires a request\n");
                 return 64;
             }
-            const response = socket.request(allocator, socket_path, line) catch {
+            const resolved_socket_path = if (std.mem.eql(u8, socket_path, "-"))
+                std.process.Environ.getAlloc(init.minimal.environ, allocator, socket.socket_env_name) catch {
+                    try stderr.writeStreamingAll(init.io, "mim: MIM_SOCKET is not set\n");
+                    return 69;
+                }
+            else
+                try allocator.dupe(u8, socket_path);
+            defer allocator.free(resolved_socket_path);
+
+            const response = socket.request(allocator, resolved_socket_path, line) catch {
                 try stderr.writeStreamingAll(init.io, "mim: mimctl request failed\n");
                 return 69;
             };