[Feat] - Update Notes and Code Block Languages

[adithyaakrishna]

Description:

• This PR changes the quoted section to use note admonitions according to docusaurus feature, https://docusaurus.io/docs/markdown-features/admonitions
• This PR also updates the code blocks across the docs to use the appropriate language to support for syntax highlighting
• This PR also adds link to the WasmEdge CNCF Sandbox Project

[adithyaakrishna]

The above commit also updates the search plugin config to index pages, along with showing the default options like,

searchBarShortcut: true,
searchBarShortcutHint: true,
searchBarPosition: "right",

[adithyaakrishna]

The notes admonitions will change the quoted section from this,

to a more visually appealing view like this,

[alabulei1]

Looks Great. Thanks for your contribution! Much appreciated.