NOISSUE - Add wasi-nn docs

[JeffMboya]

What type of PR is this?

Documentation update - adds wasi-nn integration guide.

What does this do?

Adds documentation for running wasi-nn (WebAssembly Neural Network) examples on Propeller, covering:

• wasi-nn overview and Propeller integration
• Prerequisites and setup steps
• Task submission workflow
• Platform-specific notes (macOS/Linux)
• Troubleshooting guide

Which issue(s) does this PR fix/relate to?

NOISSUE

Have you included tests for your changes?

N/A - documentation only.

Did you document any new/modified features?

Yes - documents the wasi-nn integration with Propeller's host runtime.

Notes

Requires creating two images in docs/images/ if using drawIO instead of mermaid diagrams.

[JeffMboya]

The code in proplet/src/runtime/host.rs automatically adds -S, nn when using external wasmtime. The docs incorrectly instruct users to add ["-S", "nn", "--dir=fixture"] in cli_args. This is redundant.

[dorcaslitunya]

@rodneyosodo suggested we add it via the task manifest. So now its either they pass the params using cli args or a task manifest

[JeffMboya]

Suggested change

	Upload the WASM binary using the upload endpoint. Make sure the path specified in file matches where the .wasm target is stored:
	Upload the WASM binary using the upload endpoint. Make sure the path specified in file matches where the `.wasm` target is stored:

[JeffMboya]

Suggested change

	`Sample Output:
	{"id":"3fc0a69a-6c1c-4944-bd71-1117e9ddcf31","name":"wasi-nn-demo2","state":0,"file":"<Encoded Wasm B64>","cli_args":["-S","nn","--dir=/home/proplet/fixture::fixture"],"daemon":false,"encrypted":false,"start_time":"0001-01-01T00:00:00Z","finish_time":"0001-01-01T00:00:00Z","created_at":"2026-01-30T14:30:35.983946888Z","updated_at":"2026-01-30T14:44:59.866850384Z"}
	`
	```
	# Sample output:
	# {
	# "id": "3fc0a69a-6c1c-4944-bd71-1117e9ddcf31",
	# "name": "wasi-nn-demo2",
	# "state": 0,
	# "file": "<Encoded Wasm B64>",
	# "cli_args": ["-S", "nn", "--dir=/home/proplet/fixture::fixture"],
	# "daemon": false,
	# "encrypted": false,
	# "start_time": "0001-01-01T00:00:00Z",
	# "finish_time": "0001-01-01T00:00:00Z",
	# "created_at": "2026-01-30T14:30:35.983946888Z",
	# "updated_at": "2026-01-30T14:44:59.866850384Z"
	# }