feat(P1): Nova rebrand — docs/decks/prose/schema-$id/release-titles (REQ-155/156/157)

Rebrand ACDL/Agentic Cloud Delivery Platform → Nova across README, docs/,
decks (markdown + mermaid .mmd + HTML), pyproject.toml name/description,
schema $id URLs (acdl.cloudinit.dev→nova.cloudinit.dev), release.yml
title/workflow-name. Nova tagline added to README header + both deck title
slides + docs/vision.md (alongside existing North Star, D-106). S&P theme
untouched (D-107). New docs/NOVA_MIGRATION.md consumer guide. Data values
(env vars, resource names, tag keys, SSM/consumer paths) left for P2-P4.

---ci---
project: acdl
phase: 1
milestone: v1.15
status: execute
---/ci---

docs/NOVA_MIGRATION.md

@@ -0,0 +1,170 @@
+# Nova Migration Guide — What Consumers Must Know
+
+> **Nova** is the new product brand for the platform formerly known as
+> **ACDL** (Agentic Cloud Delivery Platform). This guide announces the
+> scheduled breaking changes coming in the rebrand rollout (Phases P2–P4)
+> and tells you exactly what to do, when, and how long you have.
+
+The product is being rebranded **A C D L → Nova**. The rebrand is staged
+across phases so that **no consumer deployment breaks during the
+transition**. Phases P2–P4 ship the breaking changes behind a **dual-read
+/ parallel-write grace period**; Phase P5 removes the fallback and the old
+names stop working. This document is the consumer-facing contract for that
+rollout.
+
+## What is NOT changing
+
+- **The Gitea repository name** (`continuous-intelligence/acdl`) is **not**
+  changing. Only the product brand is changing. The `uses:` reference
+  (`acdl/.github/workflows/deploy.yml@vX.Y`) and the GitHub `acdl/acdl` repo
+  path are unchanged for the duration of the rebrand; the workflow
+  `uses:` reference will be migrated in a later, separately-announced step.
+- **The platform behavior** is unchanged. Same pipeline stages, same
+  contract schema, same confidence model, same evidence stream, same
+  modules. Only the brand, the on-disk path, the env var names, the SSM
+  path, the AWS tag keys, and the AWS resource names are changing.
+
+## The 5 breaking changes
+
+Five things that consumers may reference are being renamed. Each is
+scheduled into a phase, ships with a grace period, and has a cutoff.
+
+### 1. Consumer contract path — Phase P2
+
+- **Old:** `.acdl/contract.yml`
+- **New:** `.nova/contract.yml`
+- **Phase:** P2 (env vars + consumer path)
+- **Grace period:** during P2–P4 the deploy workflow reads **both** paths
+  (`.nova/contract.yml` first, falling back to `.acdl/contract.yml` if the
+  new path is absent). Your existing contracts keep working until P5.
+- **Cutoff:** P5 removes the `.acdl/` fallback. Move your contract file
+  before P5.
+- **What you must do:** rename the directory in your consumer repo from
+  `.acdl/` to `.nova/` and update any `contract:` workflow input that
+  points at the old path. Nothing else changes in the contract content.
+
+### 2. Environment variables — Phase P2
+
+- **Old:** `ACDL_*` (e.g. `ACDL_LIFECYCLE_MODE`, `ACDL_AWS_ACCOUNT_ID`,
+  `ACDL_BOOTSTRAP_AWS_ACCESS_KEY_ID`, …)
+- **New:** `NOVA_*` (e.g. `NOVA_LIFECYCLE_MODE`, `NOVA_AWS_ACCOUNT_ID`,
+  `NOVA_BOOTSTRAP_AWS_ACCESS_KEY_ID`, …)
+- **Phase:** P2 (env vars + consumer path)
+- **Grace period — dual-read fallback:** during P2–P4 the platform reads
+  **`NOVA_*` first, then falls back to `ACDL_*`** if the Nova variable is
+  unset. This means your CI secrets, workflow env blocks, and local
+  `.env.secrets` keep working unchanged through P4. You do not need to
+  rename everything in one shot — rename a variable and the dual-read picks
+  it up; leave one old and it still resolves.
+- **Cutoff:** P5 removes the `ACDL_*` fallback. After P5, only `NOVA_*`
+  is read.
+- **What you must do:** rename your `ACDL_*` CI secrets, workflow `env:`
+  blocks, and any local `.env.secrets` entries to `NOVA_*`. Because of the
+  dual-read, you can do this incrementally across P2–P4 — but it must be
+  complete before P5.
+
+### 3. SSM parameter path — Phase P3
+
+- **Old:** `/acdl/{env}/{contractId}/{output}`
+- **New:** `/nova/{env}/{contractId}/{output}`
+- **Phase:** P3 (SSM paths + tag keys)
+- **Grace period — parallel-write:** during P3–P4 the platform **writes
+  every output to both** the `/acdl/…` and `/nova/…` SSM paths, and reads
+  from `/nova/…` first (falling back to `/acdl/…`). Any hardcoded SSM path
+  reads in your application code keep resolving through P4.
+- **Cutoff:** P5 stops writing to `/acdl/…` and removes the read fallback.
+  After P5 only `/nova/…` exists.
+- **What you must do:** if your application code or runbooks read deploy
+  outputs from SSM by hardcoded path, update the path prefix from `/acdl/`
+  to `/nova/`. If you consume outputs only via the PR-comment / GitHub
+  issue surface, you do nothing — the platform republishes under the new
+  path automatically.
+
+### 4. AWS tag keys — Phase P3
+
+- **Old:** `acdl:owner`, `acdl:environment`, `acdl:contract`,
+  `acdl:cost-center`, `acdl:ref`
+- **New:** `nova:owner`, `nova:environment`, `nova:contract`,
+  `nova:cost-center`, `nova:ref`
+- **Phase:** P3 (SSM paths + tag keys)
+- **Grace period — parallel-tag period:** during P3–P4 the platform
+  **tags every resource with both** the `acdl:*` and `nova:*` keys (same
+  values). The ABAC session policy matches on **either** key set, so your
+  existing scoped permissions keep working. The default cost-center value
+  moves from `acdl-default` to `nova-default` (both written during the
+  parallel-tag period).
+- **Cutoff:** P5 stops writing the `acdl:*` keys and the ABAC policy matches
+  only on `nova:*`. After P5, resources created before P5 still carry the
+  old `acdl:*` tags (tags are not retroactively rewritten) but **new**
+  resources are tagged `nova:*` only, and the policy no longer grants
+  access via `acdl:*`.
+- **What you must do:** if you have IAM policies, Cost Explorer filters,
+  or billing groupings that key off `acdl:*` tag keys, add a parallel
+  `nova:*` condition (or migrate to `nova:*`) before P5. The platform
+  handles the dual-tagging; you only need to update your own tag-key
+  references.
+
+### 5. AWS resource names — Phase P4
+
+- **Old:** `acdl-*` (DynamoDB tables `acdl-contracts`,
+  `acdl-change-requests`; Lambda `acdl-contract-ingestor`; SNS
+  `acdl-sod-halt`; security group `acdl-ecs-sg`; KMS alias
+  `alias/acdl-platform`; ECS services, ECR repos, IAM user
+  `acdl-spike-runner`, state bucket `acdl-tfstate-*`, ALB `acdl-alb`,
+  `acdl-deploy-*`)
+- **New:** `nova-*` (the same resources, prefixed `nova-`)
+- **Phase:** P4 (resource names) — **maintenance window**
+- **Grace period:** P4 is a **planned maintenance window**. AWS resources
+  cannot be renamed in place, so P4 provisions the `nova-*` resources,
+  migrates data (DynamoDB tables, S3 state), repoints the platform, and
+  tears down the `acdl-*` resources. The platform team schedules and
+  announces the window; consumers do not provision or rename anything
+  themselves.
+- **Cutoff:** the `acdl-*` resources are decommissioned at the end of the
+  P4 maintenance window. After P4, only `nova-*` resources exist.
+- **What you must do:** nothing for the resource names themselves — the
+  platform owns the rename. If your application code or runbooks reference
+  a specific `acdl-*` resource by name (e.g. a hardcoded DynamoDB table
+  name or ECR URI), update it to the `nova-*` name during P4. The platform
+  publishes the exact old → new name mapping with the P4 announcement.
+
+## Timeline at a glance
+
+| Phase | What ships | Grace period | Cutoff |
+|-------|------------|--------------|--------|
+| **P1** (this phase) | Brand prose, docs, decks, schema `$id`, release titles | n/a (prose only) | n/a |
+| **P2** | `.nova/` contract path + `NOVA_*` env vars | dual-read: `.nova/`→`.acdl/`, `NOVA_*`→`ACDL_*` | **P5** removes fallback |
+| **P3** | `/nova/` SSM path + `nova:*` tag keys | parallel-write (SSM) + parallel-tag (ABAC matches either) | **P5** removes old path/tags |
+| **P4** | `nova-*` AWS resource names | maintenance window (platform-owned migration) | end of P4 window |
+| **P5** | Fallback removal | — | `ACDL_*` env vars, `.acdl/` path, `/acdl/` SSM, `acdl:*` tags stop working |
+
+## What consumers must do (checklist)
+
+1. **Before P5 — contract path:** move `.acdl/contract.yml` →
+   `.nova/contract.yml` in your consumer repo; update the `contract:`
+   workflow input. *(Can be done any time in P2–P4.)*
+2. **Before P5 — env vars:** rename `ACDL_*` CI secrets / workflow `env:`
+   blocks / local `.env.secrets` to `NOVA_*`. *(Incremental during P2–P4;
+   dual-read keeps you green.)*
+3. **Before P5 — SSM reads:** if you read deploy outputs from SSM by
+   hardcoded `/acdl/…` path, update to `/nova/…`. *(Skip if you consume
+   outputs via PR comments only.)*
+4. **Before P5 — tag-key references:** if you have IAM policies, Cost
+   Explorer filters, or billing groupings keyed off `acdl:*`, add or
+   migrate to `nova:*`. *(Platform handles dual-tagging.)*
+5. **During P4 — resource-name references:** if your code or runbooks
+   reference a specific `acdl-*` AWS resource by name, update to the
+   `nova-*` name per the P4 mapping announcement. *(Platform owns the
+   rename itself.)*
+
+## Questions
+
+If anything in this guide is unclear, or you are unsure whether your
+consumer repo references a renamed value, open an issue on the platform
+repo. The platform team will confirm what you need to change and when.
+
+> **Note:** the real Gitea repository name (`continuous-intelligence/acdl`)
+> is **not** changing — only the product brand. The `uses:` workflow
+> reference and repo path are migrated in a separately-announced later step;
+> until then, keep your `uses: acdl/.github/workflows/deploy.yml@vX.Y`
+> reference as-is.