devcontainer and various tweaks

README.md

@@ -77,18 +77,22 @@ This server currently provides MTA-STS protection for:
 
 ```
 .
-├── Dockerfile                    # Docker image definition
-├── docker-compose.yml           # Portainer stack configuration
-├── package.json                 # Build and push scripts
+├── .devcontainer/
+│   └── devcontainer.json       # Dev Container config (pnpm + Docker)
+├── .dockerignore               # Docker build context exclusions
+├── .gitignore                  # Git exclusions
+├── Dockerfile                  # Docker image definition
+├── docker-compose.yml         # Portainer stack configuration
+├── package.json               # Build and push scripts (pnpm)
 ├── nginx/
-│   └── default.conf            # nginx server configuration
+│   └── default.conf           # nginx server configuration
 ├── html/
-│   ├── index.html              # Landing page
+│   ├── index.html             # Landing page
 │   └── .well-known/
-│       └── mta-sts.txt         # MTA-STS policy file
+│       └── mta-sts.txt        # MTA-STS policy file
 └── .woodpecker/
-    ├── build.yaml              # CI: Build and push image
-    └── deploy.yaml             # CI: Trigger Portainer webhook
+    ├── build.yaml             # CI: Build and push image
+    └── deploy.yaml            # CI: Trigger Portainer webhook
 ```
 
 ## Setup & Deployment
@@ -96,10 +100,24 @@ This server currently provides MTA-STS protection for:
 ### Prerequisites
 
 - Docker installed and logged into `git.mifi.dev`
-- pnpm (for manual builds)
+- pnpm (for manual builds) — see [Package manager](#package-manager)
 - Access to the Gitea package registry
 - Portainer webhook configured (for deployments)
 
+### Package Manager
+
+This project uses **pnpm** as the package manager. The version is pinned in `package.json` via the `packageManager` field. If you use [Corepack](https://nodejs.org/api/corepack.html) (bundled with Node.js 22+), run `corepack enable` once and the correct pnpm version will be used automatically.
+
+### Dev Container (Optional)
+
+A [Dev Container](https://containers.dev/) configuration is included for consistent local development. It provides:
+
+- Node.js 24 with pnpm 10.28
+- Docker CLI with access to the host Docker daemon (so you can run `pnpm build` and test images)
+- VS Code extensions: Docker, Prettier
+
+**To use:** Open the repo in VS Code or Cursor, install the "Dev Containers" extension if needed, and run **Dev Containers: Reopen in Container** from the command palette. The first build may take a few minutes.
+
 ### Local Development
 
 1. **Clone the repository**:
@@ -108,17 +126,24 @@ This server currently provides MTA-STS protection for:
    cd mta-sts
    ```
 
-2. **Build the Docker image**:
+2. **Preview the site locally** (optional):
+   ```bash
+   pnpm install
+   pnpm dev
+   ```
+   Open http://localhost:3000 for the landing page and http://localhost:3000/.well-known/mta-sts.txt for the policy file.
+
+3. **Build the Docker image**:
    ```bash
    pnpm build
    ```
 
-3. **Test locally**:
+4. **Test locally** (with the built image):
    ```bash
    docker run -p 8080:80 git.mifi.dev/mifi-holdings/mta-sts:latest
    ```
    
-   Visit `http://localhost:8080` to see the landing page and `http://localhost:8080/.well-known/mta-sts.txt` for the policy file.
+   Visit http://localhost:8080 to see the landing page and http://localhost:8080/.well-known/mta-sts.txt for the policy file.
 
 ### Manual Deployment
 
@@ -183,6 +208,7 @@ To add MTA-STS support for a new domain:
 
 | Script | Description |
 |--------|-------------|
+| `pnpm dev` | Start local dev server for `html/` at http://localhost:3000 |
 | `pnpm build` | Build Docker image locally |
 | `pnpm push` | Push Docker image to registry |
 | `pnpm build:push` | Build and push in one command |
@@ -214,6 +240,22 @@ The container includes health checks that:
 
 ## Troubleshooting
 
+### `pnpm install` shows DEP0169 / `url.parse()` deprecation warning
+
+On **Node.js 24+**, you may see:
+
+```text
+DeprecationWarning: `url.parse()` behavior is not standardized...
+```
+
+This comes from pnpm (and its dependencies), not from this repo. The project has no runtime dependencies, so the warning is harmless and can be ignored. To hide it for a single run:
+
+```bash
+NODE_OPTIONS='--no-deprecation' pnpm install
+```
+
+To suppress it for your shell session: `export NODE_OPTIONS='--no-deprecation'`. See [pnpm#9492](https://github.com/pnpm/pnpm/issues/9492) for upstream progress.
+
 ### Container won't start
 - Check Portainer logs for the `mta-sts` container
 - Verify the image was pushed successfully to the registry