[WIP] Fix FunctionsHttpPort placeholder to show example input

[Copilot]

Thanks for asking me to work on this. I will get started on it and keep this PR's description up to date as I form a plan and make progress.

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This section details on the original issue you should resolve

<issue_title>FunctionsHttpPort placeholder shows parameter name instead of sample input</issue_title>
<issue_description>OS: Win 11 x64
Build Version: 20260507.1

Repro Steps:

1. Run "Azure Functions: Create New Project" with C# "Azure Functions" template.
2. Proceed through the workflow until the step “Port number to use for the HTTP endpoint in launchSettings.json”.
3. Observe the input field placeholder.

Expect:
The input field should provide a clear indication of the expected value, for example: 7071.

Actual:
The placeholder displays: FunctionsHttpPort. No example value or hint is provided.

More Info:

1. This appears to be a UX issue (placeholder content) rather than a functional issue
2. Related to the same workflow as #4990, but focuses specifically on input clarity
3. Improving the placeholder would make the experience more intuitive and reduce confusion</issue_description>

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