feat: mount the five-seat Bash v1 chain

bin/cb-agent-run.sh

@@ -7,13 +7,13 @@
 #   READING GUIDE
 #   -------------
 #   1. Universal input validation   <- contain paths and identify the adapter.
-#   2. Config and Git preflight     <- fail closed before tool execution.
+#   2. Custody/config/Git preflight <- consume the Launcher handoff exactly once.
 #   3. Isolated tool invocation     <- direct prompt or bounded GNHF loop.
 #   4. Candidate normalization      <- publish exact local SHA or stable error.
 #
 #   MAIN FLOW
 #   ---------
-#   step input -> config/Git preflight -> isolated tool -> Git facts -> output
+#   step input -> Launcher custody -> config/Git preflight -> tool -> output
 #
 #   PUBLIC API
 #   ----------
@@ -22,10 +22,10 @@
 #   INTERNALS
 #   ---------
 #   usage, fail_contract, publish_outcome, reject, valid_config,
-#   build_environment, install_git_guard
+#   build_environment, install_git_guard, canonical_git_common
 #
 # @exports none
-# @deps bash, env, git, jq, realpath
+# @deps bash, env, git, jq, realpath, stat
 set -euo pipefail
 
 usage() {
@@ -166,12 +166,8 @@ valid_config() {
           (explode|all(.[]; .!=0)));
       .config |
       type=="object" and
-      keys==["argv","base_sha","branch","environment","output_schema",
-        "prompt","schema","worktree"] and
+      keys==["argv","environment","output_schema","prompt","schema"] and
       .schema=="combo.coder/direct-agent/v1" and
-      (.worktree|type=="string" and startswith("/")) and
-      (.base_sha|type=="string" and test("^[0-9a-f]{40}([0-9a-f]{24})?$")) and
-      (.branch|type=="string" and length>0) and
       (.argv|strings and
         all(.[]; ((.=="--push" or startswith("--push="))|not))) and
       (.prompt|type=="string" and length>0) and
@@ -196,13 +192,10 @@ valid_config() {
           (explode|all(.[]; .!=0)));
       .config |
       type=="object" and
-      keys==["agent","argv","base_sha","branch","current_branch",
-        "environment","max_iterations","meteor_frequency","output_schema",
-        "prevent_sleep","prompt","schema","stop_when","worktree"] and
+      keys==["agent","argv","current_branch","environment","max_iterations",
+        "meteor_frequency","output_schema","prevent_sleep","prompt","schema",
+        "stop_when"] and
       .schema=="combo.coder/gnhf/v1" and
-      (.worktree|type=="string" and startswith("/")) and
-      (.base_sha|type=="string" and test("^[0-9a-f]{40}([0-9a-f]{24})?$")) and
-      (.branch|type=="string" and length>0) and
       (.argv|strings and
         all(.[]; ((.=="--push" or startswith("--push="))|not))) and
       (.prompt|type=="string" and length>0) and
@@ -234,22 +227,87 @@ if ! valid_config; then
   fi
 fi
 
-worktree=$(jq -r '.config.worktree' "$input")
-base_sha=$(jq -r '.config.base_sha' "$input")
-branch=$(jq -r '.config.branch' "$input")
+run_dir=$(jq -r '.paths.run_dir' "$input")
+[ -d "$run_dir" ] && [ ! -L "$run_dir" ] \
+  || reject "custody:run_dir_invalid"
+run_root=$(realpath "$run_dir" 2>/dev/null) \
+  || reject "custody:run_dir_invalid"
+[ "$run_root" = "$run_dir" ] || reject "custody:run_dir_invalid"
+case "$invocation_root" in "$run_root"/steps/*/attempt-"$attempt") ;;
+  *) reject "custody:run_dir_invalid" ;;
+esac
+
+ownership=$run_root/agents/launcher.ownership.json
+if [ ! -e "$ownership" ] && [ ! -L "$ownership" ]; then
+  reject "custody:missing"
+fi
+[ -f "$ownership" ] && [ ! -L "$ownership" ] \
+  || reject "custody:invalid"
+[ "$(realpath "$ownership" 2>/dev/null || true)" = "$ownership" ] \
+  || reject "custody:invalid"
+ownership_mode=$(stat -c '%a' "$ownership" 2>/dev/null \
+  || stat -f '%Lp' "$ownership" 2>/dev/null || true)
+[ "$ownership_mode" = 444 ] || reject "custody:not_read_only"
+if ! jq -e --arg run "$run_id" '
+  def sha:
+    type=="string" and test("^[0-9a-f]{40}([0-9a-f]{24})?$");
+  def text:
+    type=="string" and length>0 and
+    (explode | all(.[]; .>=32 and .!=127));
+  type=="object" and
+  .run==$run and
+  (.runway_kind=="treehouse" or .runway_kind=="git-worktree-explicit") and
+  (.repo_dir|text and startswith("/")) and
+  (.worktree|text and startswith("/")) and
+  (.branch|text) and (.base_sha|sha) and
+  if .runway_kind=="treehouse" then
+    keys==[
+      "base_sha","branch","lease_id","repo_dir","run","runway_kind","worktree"
+    ] and .lease_id==$run
+  else
+    keys==[
+      "base_sha","branch","ownership_id","repo_dir","run","runway_kind",
+      "worktree"
+    ] and .ownership_id==("git-worktree:" + $run)
+  end
+' "$ownership" >/dev/null 2>&1; then
+  reject "custody:invalid"
+fi
+
+repo_dir=$(jq -r '.repo_dir' "$ownership")
+worktree=$(jq -r '.worktree' "$ownership")
+base_sha=$(jq -r '.base_sha' "$ownership")
+branch=$(jq -r '.branch' "$ownership")
+[ -d "$repo_dir" ] && [ ! -L "$repo_dir" ] \
+  || reject "custody:repo_mismatch"
+[ "$(realpath "$repo_dir" 2>/dev/null || true)" = "$repo_dir" ] \
+  || reject "custody:repo_mismatch"
 [ -d "$worktree" ] && [ ! -L "$worktree" ] \
-  || reject "config:unsafe_worktree"
+  || reject "custody:worktree_mismatch"
 worktree_root=$(realpath "$worktree" 2>/dev/null) \
-  || reject "config:unsafe_worktree"
-[ "$worktree_root" = "$worktree" ] || reject "config:unsafe_worktree"
+  || reject "custody:worktree_mismatch"
+[ "$worktree_root" = "$worktree" ] || reject "custody:worktree_mismatch"
 [ "$(git -C "$worktree" rev-parse --show-toplevel 2>/dev/null || true)" = "$worktree" ] \
-  || reject "config:not_worktree_root"
+  || reject "custody:worktree_mismatch"
+canonical_git_common() {
+  local directory=$1 common
+  common=$(git -C "$directory" rev-parse --git-common-dir 2>/dev/null) \
+    || return 1
+  case "$common" in
+    /*) realpath "$common" 2>/dev/null ;;
+    *) realpath "$directory/$common" 2>/dev/null ;;
+  esac
+}
+repo_common=$(canonical_git_common "$repo_dir" || true)
+worktree_common=$(canonical_git_common "$worktree" || true)
+[ -n "$repo_common" ] && [ "$worktree_common" = "$repo_common" ] \
+  || reject "custody:repo_mismatch"
 git check-ref-format --branch "$branch" >/dev/null 2>&1 \
-  || reject "config:invalid_branch"
+  || reject "custody:invalid"
 [ "$(git -C "$worktree" symbolic-ref --quiet --short HEAD 2>/dev/null || true)" = "$branch" ] \
-  || reject "candidate:branch_mismatch"
+  || reject "custody:branch_mismatch"
 git -C "$worktree" cat-file -e "$base_sha^{commit}" 2>/dev/null \
-  || reject "config:base_commit_missing"
+  || reject "custody:base_mismatch"
 
 pre_head=$(git -C "$worktree" rev-parse HEAD 2>/dev/null) \
   || reject "candidate:head_unreadable"

bin/cb-chain.sh

@@ -6,26 +6,27 @@
 #   READING GUIDE
 #   -------------
 #   1. Plan validation and publication guard <- freeze the traversal boundary.
-#   2. invoke_step and fold helpers           <- universal adapter interaction.
+#   2. invoke_step and fold helpers           <- endpoint-backed adapter interaction.
 #   3. Coder/Reviewer loop                    <- same-input full-round fold.
 #   4. Gate, Cleaner, and result publication  <- preserve terminal + cleanup.
 #
 #   MAIN FLOW
 #   ---------
-#   plan -> Launcher -> Coder <-> Reviewer* -> Gate -> Cleaner -> chain result
+#   plan -> role endpoints -> Launcher -> Coder <-> Reviewer* -> Gate -> Cleaner
 #
 #   PUBLIC API
 #   ----------
 #   cb-chain.sh <runId>  Execute the plan and print immutable result path.
 #
 #   INTERNALS
 #   ---------
-#   usage, fail_contract, invoke_step, merge_result_artifacts,
+#   usage, fail_contract, resolve_effective_attempt, invoke_step,
+#   merge_result_artifacts,
 #   add_findings_artifact, record_reviewer_failure, set_terminal_from_result,
 #   set_invocation_failure, cleanup
 #
 # @exports none
-# @deps bash, jq, realpath, bin/cb-step.sh
+# @deps bash, jq, realpath, bin/cb-step.sh, optional bin/cb-run.sh dispatcher
 set -euo pipefail
 
 usage() {
@@ -106,6 +107,16 @@ script_dir=$(CDPATH='' cd -- "$(dirname "${BASH_SOURCE[0]}")" && pwd)
 step_runner=$script_dir/cb-step.sh
 [ -f "$step_runner" ] && [ ! -L "$step_runner" ] \
   || fail_contract "step runner is missing or unsafe" 73
+dispatcher=${CB_CHAIN_DISPATCHER:-}
+if [ -n "$dispatcher" ]; then
+  case "$dispatcher" in /*) ;; *)
+    fail_contract "endpoint dispatcher path must be absolute" 73 ;;
+  esac
+  [ -f "$dispatcher" ] && [ ! -L "$dispatcher" ] && [ -x "$dispatcher" ] \
+    || fail_contract "endpoint dispatcher is missing or unsafe" 73
+  [ "$(realpath "$dispatcher" 2>/dev/null)" = "$dispatcher" ] \
+    || fail_contract "endpoint dispatcher path must be canonical" 73
+fi
 
 max_rounds=${CB_CHAIN_MAX_REVIEW_ROUNDS:-20}
 case "$max_rounds" in ''|0|0*|*[!0-9]*) fail_contract "invalid max review rounds" ;; esac
@@ -117,18 +128,56 @@ reviewer_degraded=$(jq -r '.reviewer.degraded' "$plan")
 reviewer_member_failures='[]'
 # -/ 1/4
 
-# -- 2/4 HELPER · Invoke universal steps and carry artifact references --
+# -- 2/4 HELPER · Invoke endpoint-backed steps and carry artifact references --
+resolve_effective_attempt() {
+  local step=$1 requested=$2 step_index ordinal safe_step step_dir effective
+  if [ -z "$dispatcher" ]; then
+    printf '%s\n' "$requested"
+    return 0
+  fi
+  step_index=$(jq -r --arg id "$step" '
+    [.steps | to_entries[] | select(.value.id==$id) | .key] |
+    if length==1 then .[0] else empty end
+  ' "$plan")
+  [ -n "$step_index" ] || return 1
+  printf -v ordinal '%02d' "$((step_index + 1))"
+  safe_step=${step//\//-}
+  step_dir=$run_root/steps/$ordinal-$safe_step
+  effective=$requested
+  while [ -e "$step_dir/attempt-$effective" ] \
+    || [ -L "$step_dir/attempt-$effective" ] \
+    || [ -e "$run_root/dispatch/jobs/$safe_step-attempt-$effective.job.json" ] \
+    || [ -L "$run_root/dispatch/jobs/$safe_step-attempt-$effective.job.json" ] \
+    || [ -e "$run_root/dispatch/$safe_step-attempt-$effective.receipt.json" ] \
+    || [ -L "$run_root/dispatch/$safe_step-attempt-$effective.receipt.json" ]; do
+    effective=$((effective + 1))
+  done
+  printf '%s\n' "$effective"
+}
+
 invoke_step() {
   local step=$1 attempt=$2 candidate=$3
-  local output status expected_root
-  local -a args=("$run" "$step" "$attempt")
+  local output status expected_root effective_attempt endpoint_role
+  effective_attempt=$(resolve_effective_attempt "$step" "$attempt") \
+    || { last_step_status=65; return 1; }
+  local -a args=("$run" "$step" "$effective_attempt")
   if [ "$candidate" != null ]; then
     args+=(--candidate-sha "$candidate")
   fi
   args+=(--prior-artifacts "$prior_artifacts")
 
   set +e
-  output=$(bash "$step_runner" "${args[@]}" </dev/null)
+  if [ -n "$dispatcher" ]; then
+    endpoint_role=$(jq -r --arg id "$step" '
+      .steps[] | select(.id==$id) | .role
+    ' "$plan")
+    output=$(
+      "$dispatcher" --dispatch "$run" "$endpoint_role" "$step" \
+        "$effective_attempt" "$candidate" "$prior_artifacts" </dev/null
+    )
+  else
+    output=$(bash "$step_runner" "${args[@]}" </dev/null)
+  fi
   status=$?
   set -e
   last_step_status=$status
@@ -145,7 +194,8 @@ invoke_step() {
     *) last_step_status=65; return 1 ;;
   esac
   if ! jq -e \
-    --arg run "$run" --arg step "$step" --argjson attempt "$attempt" '
+    --arg run "$run" --arg step "$step" \
+    --argjson attempt "$effective_attempt" '
       .schema=="combo.step-output/v1" and .run_id==$run and
       .step_id==$step and .attempt==$attempt
     ' "$output" >/dev/null 2>&1; then
@@ -260,6 +310,10 @@ else
   set_invocation_failure launcher
   terminal_set=1
 fi
+if [ "$terminal_set" -eq 0 ] \
+  && [ "${CB_CHAIN_STOP_AFTER_ROLE:-}" = launcher ]; then
+  exit 130
+fi
 
 coder_attempt=0
 review_round=0