fix(ui): redirect to /blog when post not found in Edit page (null-value stuck loading)

[mpaulosky]

Problem

When GetBlogPostByIdQuery returns Result.Ok<BlogPostDto?>(null) (post doesn't exist), Edit.razor's OnParametersSetAsync sets _model = null and leaves _error as null. The template's @if (_model is null && _error is null) then renders 'Loading...' indefinitely.

This bug was identified in the Copilot review of PR #304 but the PR was merged before it was addressed.

Fix

Change the null-value branch from _model = null to Navigation.NavigateTo("/blog"); return;, matching the non-owner/non-admin redirect pattern.

Acceptance

• Edit.razor redirects to /blog when post is not found
• bUnit test EditRedirectsToBlogWhenPostNotFound passes

[github-actions]

📋 Assigned to Ralph (Meta)

Issue: #307 — fix(ui): redirect to /blog when post not found in Edit page (null-value stuck loading)

Ralph will pick this up in the next Copilot session.

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Otherwise, start a Copilot session and say:
Ralph, work on issue #307