fix(agents): scrub GRAPH_STATE* from adversary verification commands; raise review-suite max_agent_depth

FIX A: run_checks.py passed no env= to Popen, so verification commands
inherited the live GRAPH_STATE/GRAPH_STATE_FILE. Every suite script's
load_state() prefers GRAPH_STATE_FILE, so when the adversary reviews a repo
whose own tests exec these scripts (this repo's R5 tests) the leaked file
silently overrode the test state -> false failures. Popen now gets an env
with all GRAPH_STATE* keys removed. The five sibling script-test helpers
(review-gauntlet, code-reviewer, finding-verifier, step-runner,
deep-research) gain .env_remove("GRAPH_STATE_FILE") for hermeticity. New
R5 test loads state via GRAPH_STATE_FILE and asserts a shell-neutral
python3 -c probe sees both vars UNSET.

FIX B: the depth check compares the child's absolute depth against the
SPAWNER's own max_agent_depth (root = 0), so under
architect(0)->sisyphus(1)->review-gauntlet(2)->code-reviewer(3) the
code-review lane faulted "Max agent depth exceeded (4/3)". Limits are now
child depth + 1 headroom along the documented chains, with the chain in a
comment next to each key: code-reviewer 3->5, domain-reviewer 2->6,
architecture-reviewer 2->4, step-runner default->4 (explicit),
review-gauntlet stays 4. domain-reviewer's file-reviewer hop is documented
but inert (can_spawn_agents unset) - left unwired by decision; noted in
config and pinned via a DOCUMENTED_BUT_UNWIRED exemption in the new
bundled-config test, which pins every value and asserts per-hop headroom +
reachability along four chains.

assets/agents/adversary/scripts/run_checks.py

@@ -25,6 +25,11 @@ its own session (start_new_session) and a timeout SIGKILLs the whole process
 group, so grandchildren of a hung command cannot linger. On non-POSIX
 platforms only the direct shell child is killed — grandchildren of a
 timed-out command may survive (documented limitation).
+
+Verification commands run with GRAPH_STATE* (GRAPH_STATE, GRAPH_STATE_FILE)
+scrubbed from their environment: the reviewed repo's own tests may exec these very
+scripts with their own GRAPH_STATE, and load_state() prefers
+GRAPH_STATE_FILE, so an inherited live state file would silently win.
 """
 
 import json
@@ -57,6 +62,7 @@ def run_one(cmd, proj, budget):
     """Run one command, hard-bounded by `budget` seconds; return its record."""
     start = time.monotonic()
     popen_kwargs = {"start_new_session": True} if os.name == "posix" else {}
+    env = {k: v for k, v in os.environ.items() if not k.startswith("GRAPH_STATE")}
     p = subprocess.Popen(
         cmd,
         shell=True,
@@ -64,6 +70,7 @@ def run_one(cmd, proj, budget):
         stdout=subprocess.PIPE,
         stderr=subprocess.PIPE,
         text=True,
+        env=env,
         **popen_kwargs,
     )
     try: