DetailsList blank render in PCF harness with NaN width / theme parse errors during local debug

[pravin080317]

When running the project locally in the PCF harness (localhost:8181) after cloning the repo, the DetailsList component does not render correctly. The grid area shows blank with only partial UI visible. I did not modify any code — I simply cloned the repo and ran it locally as per the instructions.

Observed behavior

• Console shows multiple errors/warnings while debugging in the harness.
• The list area does not render properly.

Console output

GET http://localhost:8181/loc/en-us/diagnosticMessages.localized.json [HTTP/1.1 404 Not Found]
GET http://localhost:8181/favicon.ico [HTTP/1.1 404 Not Found]

Warning: `NaN` is an invalid value for the `width` css style property.
    in div (created by h)
    in div (created by h)
    in h (created by y)
    in div (created by y)
    ...

Cannot parse theme SyntaxError: JSON.parse: unexpected character at line 1 column 1 of the JSON data
    theme Grid.tsx:181
    Grid Grid.tsx:179
    ...

Warning: A component is changing a controlled input of type number to be uncontrolled.
    in input (created by l)
    ...

Warning: Received NaN for the `value` attribute. If this is expected, cast the value to a string.
    in input (created by l)
    ...

Steps to reproduce

1. Clone the repository.
2. Run locally with the PCF harness (npm start / equivalent).
3. Open http://localhost:8181 in browser.
4. Observe the blank area where the DetailsList should render.
5. Open console → see errors/warnings above.

Environment

• Browser: Chrome / Firefox (both show same issue)
• Localhost harness: http://localhost:8181
• Repo: cloned directly, no code changes
• Fluent UI version: as included in repo (v8)
• React: version bundled in repo

Expected
DetailsList should render without NaN width values or theme parsing errors.

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[pravin080317]

fullerror.txt
attached is the full console error list