Serve docs content images from shared R2 bucket instead of git

Content images under content/docs/images/ were committed as binary
files and referenced from MDX with relative paths (../images/foo.png).
fumadocs-mdx's static-export bundler resolved those at build time into
content-hashed files, which meant the image bytes had to be physically
present in the repo just to run `next build`. That's a growing repo
and doesn't fit the shared image-hosting setup other Abstract Machines
properties are moving to (a single R2 bucket, proxied same-origin so
URLs don't change, with immediate cache purge on update).

Since this site is a pure Next.js static export with no server runtime
in production (deployed as Cloudflare static assets, no next-on-pages
or opennextjs/cloudflare), there's no Next.js request handler to reach
an R2 binding from. Instead, wrangler.jsonc now has a `main` Worker
script that falls back from the ASSETS binding (only when no static
file matches, since run_worker_first defaults to false) to reading
`/docs/hardware/img/*` straight out of the shared `websites-images`
bucket, under the `hardware-docs` key prefix.

The first pass of this migration also changed MDX authoring syntax
(relative paths -> absolute `/img/<file>`) and added a
width/height JSON manifest (src/lib/image-dimensions.json) rendered
through next/image, so every new image required a manual manifest
entry or the build would throw. That's more ceremony than this change
should require: authors should keep writing plain markdown image
syntax with whatever relative path they always used, and nothing about
next/image's optimizer is actually usable here anyway (this is a
static export with no image-optimization server, `unoptimized` was
already set).

This commit reverts the MDX content and syntax to their original form
and replaces DocImage/next/image with a plain, zoomable `<img>`:

- content/docs/**/*.mdx: reverted to the original relative-path
  markdown image syntax (`../images/foo.png`)
- src/lib/remark-doc-images.ts: new remark plugin that resolves each
  image's relative path against content/docs/images/ at compile time
  (pure path math, no image bytes needed) into the literal
  `/docs/hardware/img/...` URL the Worker serves — replaces
  fumadocs-mdx's remarkImage, which needs the file on disk
- source.config.ts: disable remarkImageOptions, wire in
  remarkDocImages
- src/mdx-components.tsx: render the `img` MDX node as a plain
  `<img>` (no next/image, no width/height) wrapped in ImageZoom for
  click-to-zoom, passing `src`/`alt` to ImageZoom itself as well as
  the inner `<img>` — ImageZoom's zoomed-in view reads its image from
  that prop directly, not from `children`
- src/components/doc-image.tsx, src/lib/image-dimensions.json:
  removed, no longer needed
- worker/index.ts, wrangler.jsonc: unchanged from the first pass
- scripts/publish-image.mjs, scripts/README.md,
  scripts/.env.publish-image.example: maintainer-only upload+purge CLI
  and its docs, unchanged from the first pass

Author: ianmuchyri

.gitignore

@@ -69,6 +69,7 @@ web_modules/
 .env
 .env.*
 !.env.example
+!scripts/.env.publish-image.example
 
 # parcel-bundler cache (https://parceljs.org/)
 .cache

README.md

@@ -19,7 +19,14 @@ This site uses:
 
 - **Next.js static export** — `next build` outputs static files to `out/`
 - **Next.js `basePath`** — generates links and assets under `/docs/hardware`
-- **Post-build nesting** — `scripts/nest-static-export.mjs` moves the export under `out/docs/hardware/` so Cloudflare static assets can serve it from the route prefix without custom Worker code
+- **Post-build nesting** — `scripts/nest-static-export.mjs` moves the export under `out/docs/hardware/` so Cloudflare static assets can serve it from the route prefix
+- **Worker script (`worker/index.ts`)** — thin `main` script in front of the static
+  assets. Almost every request is served by the `ASSETS` binding untouched
+  (`run_worker_first` defaults to `false`, so Cloudflare only invokes the Worker when no
+  static file matches). The one exception is `/docs/hardware/img/*`, which the Worker
+  answers directly from the shared R2 bucket (`IMAGES_BUCKET`) — see
+  [`scripts/README.md`](./scripts/README.md) for why docs content images are no longer
+  committed to this repo.
 
 ### Cloudflare build settings (Dashboard)
 
@@ -46,8 +53,11 @@ flowchart LR
 
   subgraph Runtime_Request_Flow
     U[Browser request] --> H[Cloudflare static asset route]
-    H --> J[Static asset lookup]
+    H -->|asset found| J[Static asset lookup]
+    H -->|no asset matches| K[worker/index.ts]
+    K -->|"/docs/hardware/img/*"| R[(R2: websites-images)]
     J --> U
+    R --> U
   end
 ```
 
@@ -73,6 +83,8 @@ Set this as a Cloudflare build variable so it is embedded into the static output
 | `src/lib/source.ts`                    | Fumadocs source adapter                  |
 | `src/lib/layout.shared.tsx`            | Shared layout options (nav, logo)        |
 | `scripts/nest-static-export.mjs`       | Moves static export under `/docs/hardware` |
+| `worker/index.ts`                      | Worker script: falls back to `ASSETS`, proxies `/docs/hardware/img/*` from R2 |
+| `scripts/publish-image.mjs`            | Maintainer-only: uploads a docs image to R2 and purges its cache (see `scripts/README.md`) |
 
 ## Learn More
 

content/docs/base-board/index.mdx

@@ -5,7 +5,7 @@ description: Modular expansion board for S0 IoT Gateway
 
 # S0 Base Board
 
-![S0 Baseboard](../images/baseboard-front.png)
+![S0 Baseboard](/img/baseboard-front.png)
 
 The **S0 Base Board** is a modular expansion board designed to power and extend the functionality of the S0 compute module. It integrates critical components for industrial IoT and smart metering applications, making it ideal for professional deployments.
 
@@ -39,7 +39,7 @@ The Base Board transforms the S0 module into a complete gateway solution. The S0
 
 ## Getting Started
 
-![Baseboard Labeled](../images/bb-label.png)
+![Baseboard Labeled](/img/bb-label.png)
 
 ### Powering the Board
 

content/docs/base-board/pinouts.mdx

@@ -5,7 +5,7 @@ description: S0 Base Board pin assignments and header descriptions
 
 # Base Board Pinouts
 
-![Baseboard Pin Sockets](../images/baseboard-pinout.svg)
+![Baseboard Pin Sockets](/img/baseboard-pinout.svg)
 
 ## DC Header Pinout (`J6`)
 

content/docs/base-board/schematics.mdx

@@ -7,30 +7,30 @@ description: S0 Base Board circuit schematics and diagrams
 
 ## Ethernet Circuit
 
-![W5500](../images/ethernet.png)
+![W5500](/img/ethernet.png)
 
-![Jack and Magnetics](../images/magneticsandjack.png)
+![Jack and Magnetics](/img/magneticsandjack.png)
 
-![Decoupling Caps](../images/decapseth.png)
+![Decoupling Caps](/img/decapseth.png)
 
 ## M-Bus Circuit
 
-![Wired M-Bus](../images/wiredmbus.png)
+![Wired M-Bus](/img/wiredmbus.png)
 
 ## SD Card Circuit
 
-![SD Card](../images/sdcard.png)
+![SD Card](/img/sdcard.png)
 
 ## Board Frame and Connectors
 
-![Board Frame](../images/baseframe.png)
+![Board Frame](/img/baseframe.png)
 
-![Board Headers](../images/baseconnectors.png)
+![Board Headers](/img/baseconnectors.png)
 
 ## Power Circuitry
 
-![Terminal Block and Battery Connector](../images/powerbase.png)
+![Terminal Block and Battery Connector](/img/powerbase.png)
 
-![Voltage Converters](../images/voltconvert.png)
+![Voltage Converters](/img/voltconvert.png)
 
-![Battery Charger](../images/battcharger.png)
+![Battery Charger](/img/battcharger.png)