holy fuck voice to agent response works kinda sorta

src/letta.zig

@@ -0,0 +1,43 @@
+const std = @import("std");
+
+const LETTA_PATH = "/home/pierre/.bun/bin/letta";
+
+/// Runs `letta -n <agent> -p <prompt>`, captures everything it writes to
+/// stdout, and returns it as an owned slice (caller frees it).
+pub fn infer(
+    io: std.Io,
+    allocator: std.mem.Allocator,
+    agent: []const u8,
+    prompt: []const u8,
+) ![]u8 {
+    var child = try std.process.spawn(io, .{
+        .argv = &.{ LETTA_PATH, "--agent", agent, "-p", prompt, "--conversation", "default", "--toolset", "default" },
+        .stdout = .pipe,
+        .stderr = .inherit, // letta's error output goes straight to your terminal
+    });
+
+    // Non-null because we asked for a pipe.
+    const stdout_file = child.stdout.?;
+
+    var output: std.ArrayList(u8) = .empty;
+    errdefer output.deinit(allocator);
+
+    var buf: [16 * 1024]u8 = undefined;
+    while (true) {
+        const n = stdout_file.readStreaming(io, &.{&buf}) catch |err| switch (err) {
+            // EOF in the new Io API: letta closed its stdout. That's success.
+            error.EndOfStream => break,
+            else => |e| return e,
+        };
+        if (n == 0) break; // defensive: never spin if a 0 ever comes back
+        try output.appendSlice(allocator, buf[0..n]);
+    }
+    const term = try child.wait(io);
+    const exited_cleanly = switch (term) {
+        .exited => |code| code == 0,
+        else => false,
+    };
+    if (!exited_cleanly) return error.LettaFailed;
+
+    return output.toOwnedSlice(allocator);
+}