docs: document create-python-app ↔ cpa-templates relationship (#144)

Closes #140

Co-authored-by: ulises-jeremias <ulises.jeremias@users.noreply.github.com>

Author: ulises-jeremias

README.md

@@ -9,7 +9,20 @@
 
 Composable scaffolding CLI for production-ready Python apps.
 
-> **Status:** bootstrapping complete. Roadmap: [#1](https://github.com/Create-Python-App/create-python-app/issues/1).
+> **Status:** CLI monorepo bootstrapped. Template bank: [`cpa-templates`](https://github.com/Create-Python-App/cpa-templates). Roadmap: [#1](https://github.com/Create-Python-App/create-python-app/issues/1).
+
+## Ecosystem
+
+| Repository | Role |
+|------------|------|
+| [create-python-app](https://github.com/Create-Python-App/create-python-app) (this repo) | CLI (`create-awesome-python-app`) and scaffolding engine (`create-python-app-core`) |
+| [cpa-templates](https://github.com/Create-Python-App/cpa-templates) | Official templates and extensions (`templates.json` catalog) |
+
+The CLI fetches the catalog from:
+
+`https://raw.githubusercontent.com/Create-Python-App/cpa-templates/main/templates.json`
+
+Override with `CPA_CATALOG_URL` for forks or local testing (`file://` supported).
 
 ## Install (preview)
 
@@ -86,4 +99,5 @@ docker run --rm create-awesome-python-app --help
 ### Reference
 
 - [uv workspaces handbook](https://pydevtools.com/handbook/how-to/how-to-set-up-a-python-monorepo-with-uv-workspaces/)
-- Node parity: [Create-Node-App/create-node-app](https://github.com/Create-Node-App/create-node-app)
+- [cpa-templates](https://github.com/Create-Python-App/cpa-templates) — template and extension bank
+- Node parity: [Create-Node-App/create-node-app](https://github.com/Create-Node-App/create-node-app) + [cna-templates](https://github.com/Create-Node-App/cna-templates)

SECURITY.md

@@ -10,3 +10,14 @@ Please open a private security advisory on GitHub or email the maintainers.
 Do not open a public issue for undisclosed vulnerabilities.
 
 OSV scanning runs via `.github/workflows/osv-scanner.yml`.
+
+## Network endpoints
+
+The CLI may fetch remote resources when scaffolding or refreshing the template catalog:
+
+| Host | Purpose | Timeout | User-Agent |
+|------|---------|---------|------------|
+| `raw.githubusercontent.com` | Template catalog `templates.json` from `cpa-templates` | 10 s | `create-awesome-python-app/<version>` |
+| `github.com` | Template and extension repositories (git clone) | — | git |
+
+Override the catalog URL with `CPA_CATALOG_URL`. Use `CPA_OFFLINE=1` / `--offline` and local `file://` URLs when working air-gapped.

docs/CPA_TEMPLATES_TRACKING.md

@@ -1,10 +1,28 @@
 # Tracking: `cpa-templates` + website
 
-Tracked by https://github.com/Create-Python-App/create-python-app/issues/44
+Previously tracked by https://github.com/Create-Python-App/create-python-app/issues/44 (closed).
 
-Checklist:
+## Status
 
-- [ ] Create `Create-Python-App/cpa-templates`
-- [ ] Seed README + `templates.json`
-- [ ] Wire catalog URL in CLI
+- [x] Create `Create-Python-App/cpa-templates`
+- [x] Seed README + `templates.json`
+- [x] `fastapi-starter` template + initial extensions
+- [x] Wire catalog URL in CLI (`CPA_CATALOG_URL`, default raw GitHub URL)
+- [x] Integration tests against `cpa-templates` checkout
 - [ ] Website (optional, later)
+
+## Repositories
+
+| Repo | URL |
+|------|-----|
+| CLI monorepo | https://github.com/Create-Python-App/create-python-app |
+| Template bank | https://github.com/Create-Python-App/cpa-templates |
+
+## CNA parity reference
+
+| CNA | CPA |
+|-----|-----|
+| `create-node-app` | `create-python-app` |
+| `cna-templates` | `cpa-templates` |
+| `cna.config.json` | `cpa.config.json` |
+| `~/.cache/cna` | `~/.cache/cpa` |