refactor: Agent.run() -> Stream -> Stream.next() -> Event

converted the main agent loop from push-based (into callbacks on a
Receiver vtable) to pull-based, where `next()` re-enters a state-machine
Stream until the next event can be returned.

1 files changed, 11 insertions, 5 deletions

diff --git a/libpanto/src/root.zig b/libpanto/src/root.zig
index a49a428..b5fab1a 100644
--- a/libpanto/src/root.zig
+++ b/libpanto/src/root.zig
@@ -2,6 +2,7 @@ const std = @import("std");
 
 pub const conversation = @import("conversation.zig");
 pub const provider = @import("provider.zig");
+pub const stream = @import("stream.zig");
 pub const agent = @import("agent.zig");
 pub const config = @import("config.zig");
 pub const sse = @import("sse.zig");
@@ -32,12 +33,17 @@ pub const ToolRegistry = tool_registry.ToolRegistry;
 pub const Config = config.Config;
 pub const ProviderConfig = config.ProviderConfig;
 
+// Re-export the pull-streaming surface for embedders.
+pub const Event = stream.Event;
+pub const Stream = agent.Stream;
+pub const Agent = agent.Agent;
+
 // Internal modules. Not part of the public API — callers drive turns via
-// `provider.streamStep(allocator, io, &config, conv, receiver)` (or via the
-// `Agent`, which holds a swappable `*const Config`). The process-global HTTP
-// client is initialized with `config.initHttp` / torn down with
-// `config.deinitHttp`. These impls are exposed here only so `refAllDecls`
-// picks up their tests.
+// the `Agent` (which holds a swappable `*const Config`): `agent.run()`
+// returns a `*Stream` whose `next()` pulls one `Event` at a time. The
+// process-global HTTP client is initialized with `config.initHttp` / torn
+// down with `config.deinitHttp`. These impls are exposed here only so
+// `refAllDecls` picks up their tests.
 const openai_chat_json = @import("openai_chat_json.zig");
 const provider_openai_chat = @import("provider_openai_chat.zig");
 const anthropic_messages_json = @import("anthropic_messages_json.zig");