User configurable templates (#6420)

Co-authored-by: Douwe Osinga <douwe@squareup.com>

crates/goose/src/context_mgmt/mod.rs

@@ -1,7 +1,7 @@
 use crate::conversation::message::{ActionRequiredData, MessageMetadata};
 use crate::conversation::message::{Message, MessageContent};
 use crate::conversation::{merge_consecutive_messages, Conversation};
-use crate::prompt_template::render_global_file;
+use crate::prompt_template::render_template;
 use crate::providers::base::{Provider, ProviderUsage};
 use crate::providers::errors::ProviderError;
 use crate::{config::Config, token_counter::create_token_counter};
@@ -294,7 +294,7 @@ async fn do_compact(
             messages: messages_text,
         };
 
-        let system_prompt = render_global_file("summarize_oneshot.md", &context)?;
+        let system_prompt = render_template("compaction.md", &context)?;
 
         let user_message = Message::user()
             .with_text("Please summarize the conversation history provided in the system prompt.");