examples: move the WASM browser demo into a top-level examples/wasm/

Finish the per-language `examples/<lang>/` restructure by relocating the
WASM browser demo from bindings/wasm/examples/ to examples/wasm/.

* `examples/wasm/index.html` is the moved file; its WASM module import
  becomes `../../bindings/wasm/pkg/wickra_wasm.js` so the demo still loads
  the wasm-pack output without copying it.
* bindings/wasm/README.md, Quickstart-WASM.md, examples/README.md and the
  root README "Languages" + project-layout block all point at the new
  path. The serve command in the docs now says "serve the repository root
  and open examples/wasm/index.html".

`bindings/wasm/examples/` is empty after the move; the now-empty
directory is removed.

README.md

@@ -119,7 +119,7 @@ inherit it automatically.
 |-------------------|-----------------------------------------------|---------|
 | Python (PyO3)     | `pip install wickra`                          | `examples/python/backtest.py` |
 | Node.js (napi-rs) | `npm install wickra`                          | `examples/node/backtest.js` |
-| Browser / WASM    | `npm install wickra-wasm`                     | `bindings/wasm/examples/index.html` |
+| Browser / WASM    | `npm install wickra-wasm`                     | `examples/wasm/index.html` |
 | Rust              | `cargo add wickra`                            | `examples/rust/src/bin/backtest.rs` |
 
 Each binding ships several runnable examples (streaming, backtest, live feed);
@@ -187,12 +187,13 @@ wickra/
 ├── bindings/
 │   ├── python/              PyO3 + maturin (publishes on PyPI)
 │   ├── node/                napi-rs (publishes on npm)
-│   └── wasm/                wasm-bindgen (browsers, bundlers, Node) + examples/
+│   └── wasm/                wasm-bindgen (browsers, bundlers, Node)
 ├── examples/                examples/README.md indexes every language
 │   ├── data/                real BTCUSDT OHLCV datasets, one per timeframe
 │   ├── rust/                Rust workspace member (`wickra-examples`)
 │   ├── python/              backtest, live trading, parallel assets, multi-tf
-│   └── node/                streaming, backtest, live trading (load `wickra`)
+│   ├── node/                streaming, backtest, live trading (load `wickra`)
+│   └── wasm/                browser demo for `wickra-wasm`
 └── .github/workflows/       CI and release pipelines
 ```