doc: add README with build, config, deployment, and OSCAR hotkey guide

Covers architecture, building, configuration, deployment, port
switching with Avocent OSCAR (tested hotkey syntax with recommended
pause settings), full hotkey syntax reference, and protocol heritage
naming the Peppercon e-RIC/LARA lineage.

Completes success criterion 5: source on git.lair.cafe with a README
that names the Peppercon e-RIC heritage.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

README.md

@@ -0,0 +1,142 @@
+# blekin
+
+A Rust proxy that translates the Belkin OmniView Remote IP Manager's proprietary
+e-RIC RFB protocol (Peppercon LARA, originally served via a Java applet) into a
+modern HTML5 KVM console. No Java anywhere in the stack.
+
+## What it does
+
+```
+Browser (Vite + TypeScript)
+   │ WebSocket (binary, RGBA blits + input events)
+   ▼
+blekin proxy (Rust, tokio + axum)
+   │ HTTP session (cookie + APPLET_ID extraction)
+   │ TCP to OmniView:443 (e-RIC RFB)
+   ▼
+Belkin OmniView Remote IP Manager → downstream KVM switch → servers
+```
+
+The proxy authenticates with the OmniView's web interface, establishes an e-RIC
+RFB session over TCP, decodes the proprietary 8bpp protocol to RGBA, and bridges
+video frames and input events to a browser-based console over WebSocket.
+
+## Features
+
+- Full KVM console: keyboard, mouse, scroll wheel
+- Encodings: Raw, CopyRect, Hextile, Tight (with zlib), IIP tile cache, Raw-tile
+- Send Key menu for browser-intercepted keys (Print Screen, Scroll Lock, etc.)
+- Port switching with downstream KVM support (Avocent OSCAR tested)
+- Port configuration: naming, hotkeys, visibility
+- Auto-reconnect with exponential backoff
+- Session persistence across page refreshes
+- Dark theme, fullscreen mode
+
+## Building
+
+```sh
+# Backend
+cargo build --release -p ericrfb-proxy
+
+# Frontend
+cd crates/ericrfb-frontend
+npm ci
+npm run build   # outputs to ../../dist/
+```
+
+## Configuration
+
+The proxy reads `config.toml` or falls back to the `BLEKIN_HOST` environment variable:
+
+```toml
+bind = "0.0.0.0:3000"
+static_dir = "dist"
+
+[omniview]
+host = "10.3.0.130"
+http_port = 80
+rfb_port = 443
+```
+
+## Deployment
+
+The systemd unit runs the proxy as a service. Nginx serves the static frontend
+and reverse-proxies `/api/` to the proxy:
+
+```sh
+# Backend
+sudo cp target/release/ericrfb-proxy /usr/local/bin/
+sudo cp asset/systemd/blekin.service /etc/systemd/system/
+sudo systemctl enable --now blekin.service
+
+# Frontend
+sudo cp -r dist/* /var/www/blekin.example.com/
+sudo cp asset/nginx/blekin.example.conf /etc/nginx/sites-available/
+sudo ln -sf /etc/nginx/sites-available/blekin.example.conf /etc/nginx/sites-enabled/
+sudo nginx -t && sudo systemctl reload nginx
+```
+
+## Port switching with downstream KVM
+
+The Belkin OmniView can control a downstream KVM switch (e.g., Avocent AutoView)
+by sending configurable hotkey sequences when switching ports. Configure these
+in the Ports page of the blekin interface.
+
+### Avocent OSCAR setup
+
+The Avocent OSCAR menu is invoked with Print Screen, then expects the port's EID
+(Electronic ID) typed as digits, followed by Enter. Each phase needs a pause to
+let the OSCAR process the input.
+
+**Recommended settings:**
+
+- **Key pause:** `1000` ms (in the Ports page global settings)
+- **Hotkey format:** `PRINTSCREEN-***<EID digits>-***ENTER`
+
+The `*` character inserts a pause of the configured duration. Three `***` = 3
+seconds, which gives the OSCAR reliable processing time.
+
+**Examples** (with key pause = 1000ms):
+
+| Server | Avocent EID | Hotkey |
+|--------|-------------|--------|
+| server-a | 01 | `PRINTSCREEN-***1-***ENTER` |
+| server-b | 05 | `PRINTSCREEN-***5-***ENTER` |
+| server-c | 17 | `PRINTSCREEN-***1-7-***ENTER` |
+| server-d | 22 | `PRINTSCREEN-***2-2-***ENTER` |
+| server-e | 31 | `PRINTSCREEN-***3-1-***ENTER` |
+
+Note: don't type the leading zero in EIDs (per Avocent OSCAR convention).
+
+### Hotkey syntax reference
+
+The Belkin hotkey syntax uses key names connected by operators:
+
+| Operator | Meaning |
+|----------|---------|
+| `+` | Press additionally (hold previous, press next) |
+| `-` | Release all pressed keys |
+| `>` | Release most recently pressed key only |
+| `*` | Pause for the configured key pause duration |
+
+Key names: `A`-`Z`, `0`-`9`, `F1`-`F12`, `PRINTSCREEN`, `ENTER`, `ESCAPE`,
+`LCTRL`/`CTRL`, `LALT`/`ALT`, `LSHIFT`/`SHIFT`, `SPACE`, `TAB`, `DELETE`,
+`INSERT`, `HOME`, `END`, `PAGE_UP`, `PAGE_DOWN`, `UP`, `DOWN`, `LEFT`, `RIGHT`,
+`BACK_SPACE`, `NUM_LOCK`, `NUMPAD0`-`NUMPAD9`, `NUMPADPLUS`, `NUMPADMINUS`,
+`NUMPADMUL`, `NUMPAD/`, `NUMPADENTER`, `SCROLL_LOCK`, `BREAK`, `CAPS_LOCK`.
+
+## Protocol heritage
+
+The e-RIC RFB protocol is a proprietary variant of VNC/RFB developed by
+Peppercon (later acquired by Raritan) under the name "LARA" (LAN Attached
+Remote Access). It was used in several KVM-over-IP products including the Belkin
+OmniView Remote IP Manager (F1DE101H). The protocol shares structural
+similarities with standard RFB but uses its own handshake, pixel format
+negotiation, and encoding extensions.
+
+This implementation was reverse-engineered from the CFR-decompiled `rc.jar` Java
+applet that originally provided the browser-based console.
+
+## License
+
+MIT