agent: move "sketch-base" into git
The agent's notion of "initial commit" is kind of special, in that it
is used as the "base" for a bunch of git operations. It's hard for
the user to change (we only provide a workflow via restart), yet
sometimes you want to do just that.
So, instead we put it as data inside of it, named as a tag sketch-base.
It's abusing tags, but branches are no better.
diff --git a/claudetool/codereview/llm_review.go b/claudetool/codereview/llm_review.go
index 32a8e00..df8af9b 100644
--- a/claudetool/codereview/llm_review.go
+++ b/claudetool/codereview/llm_review.go
@@ -17,7 +17,7 @@
// doLLMReview analyzes the diff using an LLM subagent.
func (r *CodeReviewer) doLLMReview(ctx context.Context) (string, error) {
// Get the full diff between initial commit and HEAD
- cmd := exec.CommandContext(ctx, "git", "diff", r.initialCommit, "HEAD")
+ cmd := exec.CommandContext(ctx, "git", "diff", r.sketchBaseRef, "HEAD")
cmd.Dir = r.repoRoot
out, err := cmd.CombinedOutput()
if err != nil {