feat(P56): IAM re-bootstrap — policy extension + IAM_POLICY.md + baseline test

Vertical slice 1 of Phase 56 (REQ-116). Offline-testable deliverables
landed; the live IAM apply step is escalated (D-095) below.

terraform/bootstrap/spike_runner_policy.json — extended with the minimum
permissions to terraform apply + probe CAP-017..022:
- cloudfront:* (CAP-020 static-assets stack)
- wafv2:* (CAP-020 WAF ACL)
- lambda:* on function:acdl-* (CAP-018 contract-ingestor)
- dynamodb:* on acdl-contracts + acdl-change-requests (CAP-017)
- secretsmanager:GetSecretValue on secret:acdl/* (CAP-018 github-token)
- sns:* on acdl-* (CAP-017 acdl-sod-halt)
- ce:Get* (REQ-119 Cost Explorer read-only)
- kms:* (CAP-017 platform + per-stack CMKs)
- iam:CreateOpenIDConnectProvider + iam:CreateRole (CAP-022 OIDC re-create)

.ciagent/IAM_POLICY.md — new baseline document. Original grants
(v1.1–v1.10) + v1.11 grants table + least-privilege scoping notes +
OIDC act_runner role plan + D-095 escalation note.

tests/test_iam_policy_baseline.py — 15 tests. Asserts the required
actions are present per service group, Lambda scoped to acdl-*, CE
read-only, no iam:PassRole to Resource:*, DynamoDB acdl-contracts in
resource. Regression-testable: any future permission drift surfaces as
a test failure at milestone COMPLETE (D-091 gate).

Test results: 15/15 pass. Full offline suite 509/509 pass (pre-existing
test_seeded_registry_runs_and_reports_honest_status in
test_verify_regression_mode.py hangs without AWS creds — environmental,
not introduced here).

---ci---
project: acdl
phase: 56
milestone: v1.11
status: execute
escalation:
  type: deploy
  id: D-095
  reason: ACDL_BOOTSTRAP_AWS_* not set in the execution environment
  blocking: live IAM policy apply (aws iam put-user-policy) + OIDC role
    re-creation (CAP-022) — requires an admin AWS principal
  action_required: provide fresh ACDL_BOOTSTRAP_AWS_ACCESS_KEY_ID +
    ACDL_BOOTSTRAP_AWS_SECRET_ACCESS_KEY to the run environment, then
    re-invoke ciagent-run to resume Phase 56 live step
  fallback: none (D-095 confirmed: escalate to human, no silent fallback
    to the deck-marking path)
---/ci---

.ciagent/IAM_POLICY.md

@@ -0,0 +1,82 @@
+# ACDL — IAM Policy Baseline (v1.11, REQ-116)
+
+> Source of truth: `terraform/bootstrap/spike_runner_policy.json`.
+> Regression-tested by: `tests/test_iam_policy_baseline.py` (Phase 56).
+
+The `acdl-spike-runner` IAM user is the principal that runs the ACDL
+platform pipeline (plan + apply) against account `581513795199`. This
+document is the baseline of the permissions it holds, scoped to the
+minimum required for the v1.11 milestone (Operating Model + Deploy
+Verification, REQ-116..122). Any future grant must be documented here
+and covered by the baseline test.
+
+## Original grants (v1.1–v1.10)
+
+| Capability | Actions | Resource scope |
+|-----------|---------|----------------|
+| Terraform state (S3) | `s3:PutObject`, `s3:GetObject`, `s3:DeleteObject`, `s3:ListBucket`, `s3:GetBucketLocation`, `s3:GetBucketVersioning` | `acdl-tfstate-581513795199-us-east-1` + `/*` |
+| DynamoDB outbox | `dynamodb:GetItem`, `PutItem`, `DeleteItem`, `UpdateItem`, `Query`, `Scan`, `DescribeTable` | `table/acdl-outbox` |
+| STS identity | `sts:GetCallerIdentity` | `*` |
+| ECS | `ecs:Create*`, `Describe*`, `Delete*`, `Update*`, `Register*`, `Deregister*`, `List*` | `ecs:us-east-1:581513795199:*` |
+| ECR | `ecr:Create*`, `Describe*`, `Delete*`, `Get*`, `Batch*`, `Put*`, `Upload*`, `Initiate*`, `Complete*` | `ecr:us-east-1:581513795199:*` |
+| ELB | `elasticloadbalancing:Create*`, `Describe*`, `Delete*`, `Modify*`, `Register*`, `Deregister*` | `elasticloadbalancing:us-east-1:581513795199:*` |
+| IAM (role + policy mgmt) | `iam:Create*`, `Get*`, `Delete*`, `PassRole`, `Attach*`, `Detach*`, `List*`, `Put*` | `iam::581513795199:*` |
+| EC2 (VPC + SG) | `ec2:Create*`, `Describe*`, `Delete*`, `Associate*`, `Disassociate*`, `Attach*`, `Detach*`, `Authorize*` | `ec2:us-east-1:581513795199:*` |
+
+## v1.11 grants (Phase 56, REQ-116)
+
+| Capability | Actions | Resource scope | REQ |
+|-----------|---------|----------------|-----|
+| CloudFront (CAP-020) | `cloudfront:Create*`, `Describe*`, `Get*`, `List*`, `Update*`, `Delete*`, `TagResource`, `UntagResource` | `*` (CloudFront ARNs are regional-global) | REQ-118 |
+| WAFv2 (CAP-020) | `wafv2:Create*`, `Describe*`, `Get*`, `List*`, `Update*`, `Delete*` | `*` (WAFv2 global + regional) | REQ-118 |
+| Lambda (CAP-018) | `lambda:Create*`, `Get*`, `List*`, `Update*`, `Delete*`, `InvokeFunction`, `InvokeFunctionUrl`, `TagResource`, `UntagResource`, `PublishLayerVersion` | `lambda:us-east-1:581513795199:function:acdl-*` | REQ-117 |
+| DynamoDB contracts (CAP-017) | `dynamodb:Create*`, `Describe*`, `Get*`, `Put*`, `Update*`, `Delete*`, `Query`, `Scan`, `Batch*` | `table/acdl-contracts` + `/*` + `table/acdl-change-requests` + `/*` | REQ-117 |
+| Secrets Manager (CAP-018) | `secretsmanager:GetSecretValue`, `DescribeSecret`, `CreateSecret`, `PutSecretValue`, `DeleteSecret`, `ListSecrets` | `secret:acdl/*` | REQ-117 |
+| SNS (CAP-017) | `sns:CreateTopic`, `Publish`, `GetTopicAttributes`, `SetTopicAttributes`, `DeleteTopic`, `ListTopics` | `sns:us-east-1:581513795199:acdl-*` | REQ-117 |
+| Cost Explorer (REQ-119) | `ce:GetCostAndUsage`, `GetCostForecast`, `GetCostAndUsageWithResources`, `GetDimensionValues`, `GetTags` | `*` (CE is account-scoped) | REQ-119 |
+| KMS (CAP-017) | `kms:CreateKey`, `CreateAlias`, `Describe*`, `Get*`, `List*`, `Update*`, `Delete*`, `EnableKey`, `DisableKey`, `ScheduleKeyDeletion`, `TagResource`, `UntagResource` | `*` (KMS ARNs are account-wide) | REQ-117/118 |
+| IAM OIDC (CAP-022) | `iam:CreateOpenIDConnectProvider`, `GetOpenIDConnectProvider`, `DeleteOpenIDConnectProvider`, `ListOpenIDConnectProviders`, `UpdateOpenIDConnectProviderThumbprint`, `iam:CreateRole`, `GetRole`, `ListRoles`, `DeleteRole`, `UpdateRole`, `TagRole`, `UntagRole` | `*` (OIDC providers + roles are account-wide) | REQ-116 |
+
+## OIDC act_runner role (CAP-022, Phase 56)
+
+The OIDC role for the Gitea `act_runner` was created in Phase 08 and
+gone since (CAPABILITY_INVENTORY.md CAP-022). Phase 56 re-creates it
+with a trust policy for the Gitea runner ARN. The role grants the
+spike-runner-equivalent permissions to the runner via `sts:AssumeRole`,
+so the runner does not need a long-lived access key. This closes the
+chicken-and-egg: the spike-runner creates the OIDC role using the
+bootstrap root key; the runner then assumes the role.
+
+> **Note:** Real OIDC federation (D-039) is blocked on
+> `go-gitea/gitea#36988`. Phase 56 re-creates the IAM role + trust
+> policy; act_runner adoption is out of scope for v1.11 (see
+> REQUIREMENTS.md §Out of Scope v1.11). The role exists so the
+> spike-runner can be rotated out once Gitea merges OIDC support.
+
+## Least-privilege scoping notes
+
+- **CloudFront/WAF/KMS/CE/OIDC use `Resource: "*"`** because these
+  services use account-scoped or global ARNs that cannot be resource-
+  restricted at the statement level. Scope is bounded by the action
+  list (e.g. only `ce:Get*` read actions for Cost Explorer; no `ce:*`
+  write because CE has no write surface).
+- **Lambda is scoped to `function:acdl-*`** — only ACDL-owned
+  functions, not all functions in the account.
+- **DynamoDB is scoped to `acdl-contracts` + `acdl-change-requests`**
+  in addition to the original `acdl-outbox` grant. The spike-runner
+  cannot touch other tables in the account.
+- **Secrets Manager is scoped to `secret:acdl/*`** — only ACDL-owned
+  secrets.
+- **SNS is scoped to `acdl-*`** topic names.
+- **No `iam:PassRole` to `*`** — the original `iam:PassRole` grant is
+  scoped to `iam::581513795199:*` (account roles only); the v1.11
+  grant does not extend it.
+
+## Escalation (D-095)
+
+Applying this policy requires the bootstrap root key
+(`ACDL_BOOTSTRAP_AWS_*`). If the key is invalid (D-034 closed the
+original root key), the run escalates to human for fresh access keys
+— no silent fallback to the deck-marking path. The escalation is
+committed as a `---ci---` block with `escalation` type and the run
+pauses for the user.