Repository: tauri
Issue: [bug] HTML encoding issue for data-url
Labels: type: bug,status: needs triage

### Describe the bug

Html content containing special characters are not properly encoded when creating a new webview window using data url.



### Reproduction

```
let html = r#"
    <html>
      <body>
       special character incoming ###
       thai characters incoming สระ
      </body>
    </html>
  "#;
  let data = format!("data:text/html,{}", html);
  let _docs_window = tauri::WindowBuilder::new(
    &handle,
    "myWindow",
    tauri::WindowUrl::External(data.parse().unwrap())
  )

  .build()
  .unwrap();
```

does not work, while reading from an external file

```
  let html = r#"
    <html>
      <body>
       special character incoming ###
       thai characters incoming สระ
      </body>
    </html>
  "#;
  std::fs::write(path.clone(), html).expect("Unable to write file");
  let data = format!("data:text/html,{}", html);
  let _docs_window = tauri::WindowBuilder::new(
    &handle,
    "myWindow",
    tauri::WindowUrl::App("external.html".parse().unwrap())
  )
  .build()
  .unwrap();
```

works

### Expected behavior

_No response_

### Full `tauri info` output

```text
[✔] Environment
    - OS: Windows 10.0.19045 X64
    ✔ WebView2: 120.0.2210.144
    ✔ MSVC: Visual Studio Build Tools 2022
    ✔ rustc: 1.74.1 (a28077b28 2023-12-04)
    ✔ cargo: 1.74.1 (ecb9851af 2023-10-18)
    ✔ rustup: 1.26.0 (5af9b9484 2023-04-05)
    ✔ Rust toolchain: stable-x86_64-pc-windows-msvc (default)
    - node: 16.16.0
    - pnpm: 6.11.0
    - yarn: 1.22.15
    - npm: 8.11.0

[-] Packages
    - tauri [RUST]: 1.5.3
    - tauri-build [RUST]: 1.5.0
    - wry [RUST]: 0.24.6
    - tao [RUST]: 0.16.5
    - @tauri-apps/api [NPM]: 1.5.1 (outdated, latest: 1.5.3)
    - @tauri-apps/cli [NPM]: 1.5.6 (outdated, latest: 1.5.9)

[-] App
    - build-type: bundle
    - CSP: unset
    - distDir: Set automatically by Vue CLI plugin
    - devPath: Set automatically by Vue CLI plugin
    - framework: Vue.js (Nuxt)
    - bundler: Webpack
```


### Stack trace

_No response_

### Additional context

After some initial investigation, and help from @i-c-b on Discord, I have identified some problems
1. data-url is not parsing html correctly at https://github.com/tauri-apps/tauri/blob/dev/core/tauri/src/manager/webview.rs#L441. 

```
    let html = r#"
        <html>
        <body>
        special character incoming ###
        thai characters incoming สระ
        </body>
        </html>
    "#;
    let data = format!("data:text/html,{}", html);
    let result = data_url::DataUrl::process(&data).unwrap();
    let (body, _) = result.decode_to_vec().unwrap();
    let res = String::from_utf8(body).unwrap();

```
Will produce 
`        <html>        <body>        special character incoming`

As a temporary workaround, we can percent encode the HTML on tauri level, before running the process function - that seems to work

```
    let html = r#"
        <html>
        <body>
        special character incoming ###
        thai characters incoming สระ
        </body>
        </html>
    "#;
    let html = urlencoding::encode(&html);
    let data = format!("data:text/html,{}", html);
    let result = data_url::DataUrl::process(&data).unwrap();
    let (body, _) = result.decode_to_vec().unwrap();
    let res = String::from_utf8(body).unwrap();
```
Will produce back the same html
`        <html>
        <body>
        special character incoming ###
        thai characters incoming สระ
        </body>
        </html>`

2. url.to_string() / to_path() converts the html into percent encoded ASCII string, which in turn is passed to the unified webview of WRY, that does encoding again on webview layer depending on the OS. As a result, the html is encoded twice on OS like windows, 
https://github.com/tauri-apps/wry/blob/dev/src/webview2/mod.rs#L842

3. On the tauri-runtime-wry layer, its using ` .with_url(&url)` even for data url with html content. There is another method ` .with_html(&html)` in wry we can make use of, for data url containing html content.