fix(TASK-046): engine polish + wizard bypass + ETXTBSY retry

- unify hook base-env assembly on hooks::base_envs_parts (drop the
  hand-copied hook_base_envs in function/agents.rs; graph executor and
  spawn-result hooks now share the single construction site, test-pinned)
- factor the duplicated job.started dispatch in jobs.rs handle_start
  into one fire_job_started helper
- COYOTE_LLM_ERROR now carries the immediate error (to_string()),
  matching COYOTE_TOOL_ERROR; test pins the new format
- remove all stale #[allow(dead_code)] markers in src/hooks.rs
- test infra: rename install_warn_collector -> install_log_collector,
  add poison-symmetric warn_snapshot/debug_snapshot helpers, hoist a
  shared EnvVarGuard (TestConfigDirGuard now builds on it), add a
  same-fire payload-uniqueness test, and give global_tools env
  overrides the same malformed-JSON debug diagnostic as global_hooks
- inspection-only flags (--info et al) bypass the first-run wizard:
  missing config + info_flag returns Config::default() without writing
  anything, in both the sandbox and interactive arms (tests included)
- bound the shim-relocation test's exec in an ETXTBSY retry (10x50ms)
- document the intended 'roles' reserved-name asymmetry at
  resolve_bundle_name's gate

src/graph/executor.rs

@@ -11,7 +11,6 @@ use super::user_interaction::{ApprovalNodeExecutor, InputNodeExecutor};
 use super::validator::{AgentValidationContext, GraphValidator};
 use super::wall_clock;
 use crate::config::{AgentVariable, AgentVariables, RenderMode, RequestContext};
-use crate::function::agents::hook_base_envs;
 use crate::hooks::{self, HookEvent, ResolvedHook};
 use crate::supervisor::mailbox::{Inbox, PeerAssignment, PeerRegistry, graph_agent_id};
 use crate::utils::{AbortSignal, wait_abort_signal, wait_user_interrupt};
@@ -550,7 +549,7 @@ impl NodeHookEmitter {
         hooks::fire_resolved(
             event,
             resolved.to_vec(),
-            hook_base_envs(
+            hooks::base_envs_parts(
                 event,
                 self.session_name.as_deref(),
                 self.agent_name.as_deref(),
@@ -1619,7 +1618,7 @@ nodes:
     /// debug log, and a well-formed sibling on the same event still fires.
     #[tokio::test]
     async fn malformed_graph_yaml_hook_is_skipped_without_breaking_the_node() {
-        crate::testing::install_warn_collector();
+        crate::testing::install_log_collector();
         let _sink = hooks::test_sink::install();
         let mut ctx = make_ctx();
 
@@ -1660,10 +1659,7 @@ nodes:
         assert_eq!(valid.len(), 1, "{valid:?}");
         assert_eq!(valid[0].envs["COYOTE_NODE_ID"], "done");
 
-        let debugs: Vec<String> = crate::testing::debug_messages()
-            .lock()
-            .unwrap_or_else(|poisoned| poisoned.into_inner())
-            .clone();
+        let debugs = crate::testing::debug_snapshot();
         assert!(
             debugs
                 .iter()