Adapt instructions based on trigger type

[mintybasil]

yoke/src/runner.rs

Lines 55 to 65 in dc47167

	fn build_instructions(workflow: &Workflow, workspace_dir: &Path) -> Option<String> {
	if workflow.git.clone || workflow.git.worktree {
	let path = workspace_dir.to_string_lossy();
	Some(format!(
	"All work is in: {}. Always run `cd {}` as your first action before any file or terminal operations. Reference all file paths relative to this directory.",
	path, path
	))
	} else {
	None
	}
	}

Currently we specify the same instructions field for the agent regardless of trigger type, and only if git.clone/git.workspace are enabled. As shown in #171 this can be problematic, and may not apply for some triggers.

We should refactor this is use trigger-specific values. Further investigation is required to determine what instructions should be used for which triggers.