tests: Add end-to-end mutation provenance regressions

Exercise Claude and Codex Bash mutation scopes through real Git commits and Agent Trace persistence to verify that model and canonical session provenance survive mutation projection.
Keep mutation protocol attribution separate from direct diff evidence while synchronizing the completed provenance contract across the affected context records.
Plan: mutation-scope-provenance (T07)

Co-authored-by: SCE <sce@crocoder.dev>

Author: davidabram

cli/src/services/hooks/claude_mutation_scope/mod.rs

@@ -384,7 +384,7 @@ pub(crate) fn run_claude_mutation_scope_from_payload(
 }
 
 #[cfg(test)]
-fn run_claude_mutation_scope_from_payload_at_state_root(
+pub(crate) fn run_claude_mutation_scope_from_payload_at_state_root(
     state_root: &Path,
     stdin_payload: &str,
     logger: Option<&dyn Logger>,

cli/src/services/hooks/codex_mutation_scope/mod.rs

@@ -359,7 +359,7 @@ pub(crate) fn run_codex_mutation_scope_from_payload(
 }
 
 #[cfg(test)]
-fn run_codex_mutation_scope_from_payload_at_state_root(
+pub(crate) fn run_codex_mutation_scope_from_payload_at_state_root(
     state_root: &Path,
     stdin_payload: &str,
     logger: Option<&dyn Logger>,

cli/src/services/hooks/mod.rs

@@ -169,7 +169,7 @@ pub fn patch_for_locations_with_provenance(
                             };
                             let provenance = selected.get(&location)?;
                             let mut line = line.clone();
-                            line.session_id = provenance.session_id.clone();
+                            line.session_id.clone_from(&provenance.session_id);
                             Some(line)
                         })
                         .collect::<Vec<_>>();