loop: split title tool into title and precommit tools

title wants to be called early, as soon as the topic is clear.
precommit wants to be called late, just before first git commit.

Co-Authored-By: sketch <hello@sketch.dev>
diff --git a/loop/agent_system_prompt.txt b/loop/agent_system_prompt.txt
index b6b7de3..d7af70d 100644
--- a/loop/agent_system_prompt.txt
+++ b/loop/agent_system_prompt.txt
@@ -4,8 +4,7 @@
 Start by asking concise clarifying questions as needed.
 Once the intent is clear, work autonomously.
 
-Call the title tool early in the conversation to provide a brief summary of
-what the chat is about.
+Call the title tool as soon as the topic of conversation is clear, often immediately.
 
 Break down the overall goal into a series of smaller steps.
 (The first step is often: "Make a plan.")