Fix batch of bugs: Dockerfile, duplicate HTML attrs, nil guards

[dyoung522]

Changes

Fixes all 4 identified bugs in one batch:

#58 — Dockerfile rewrite

• Multi-stage build (build stage + slim runtime stage)
• Removed Node.js and Yarn (not needed with importmaps)
• Runs as non-root user
• Significantly smaller image

#59 — Duplicate class attribute in _mod.html.erb

• Merged duplicate class attributes into one
• Kept the cursor-pointer and lighter hover styles

#62 — Duplicate </header> in layout

• Removed inline </header> that caused a stray closing tag

#64 — Analytics partial nil guards + CSS bug

• Added nil checks for metadata, metadata[:errors], metadata[:warnings]
• Fixed type == :error → type == :errors so red CSS actually applies to errors
• Added safe navigation (&.dig) in show view
• Graceful fallback when no analytics data available

Closes #58, closes #59, closes #62, closes #64

[Copilot]

Pull request overview

This PR batches several fixes across the Rails app’s views and containerization to address broken/stale Docker builds, invalid HTML, and analytics rendering edge cases.

Changes:

• Rewrites the Dockerfile to a multi-stage build, removes Node/Yarn, and runs the app as a non-root user.
• Fixes invalid HTML in views (duplicate class attribute, stray </header>).
• Adds nil-guarding/fallback rendering for analytics metadata and corrects error vs warning CSS targeting.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
Dockerfile	Switches to multi-stage build with slimmer runtime image and non-root execution.
app/views/mods/_mod.html.erb	Removes duplicate class attribute by merging classes.
app/views/layouts/application.html.erb	Fixes malformed header markup by removing an extra closing tag.
app/views/mods/_analytics.html.erb	Adds guards/fallback UI for missing analytics data and fixes error styling condition.
app/views/mods/show.html.erb	Uses safe navigation when passing analytics metadata to the partial.

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[Copilot]

The extra && @mod.metadata.present? guard prevents rendering the analytics partial when @mod.metadata is nil, so the partial can’t show its new "No analytics data available" fallback. Consider rendering whenever params[:analytics] is set and pass @mod.metadata&.dig(:status) (letting the partial handle nil).

Suggested change

	<%= render("analytics", metadata: @mod.metadata&.dig(:status)) if params[:analytics] && @mod.metadata.present? %>
	<%= render("analytics", metadata: @mod.metadata&.dig(:status)) if params[:analytics] %>

[Copilot]

This change is intended to make analytics rendering resilient to missing metadata, but the existing request specs only cover the case where metadata[:status] is present. Please add a request spec for analytics=true when @mod.metadata (or metadata[:status]) is nil/blank to assert the fallback behavior (e.g., "No analytics data available").

[Copilot]

The image now runs as the non-root rails user, but the deployment config mounts a named volume at /rails/tmp (config/deploy.yml). Docker volumes are typically owned by root on first create, which can cause runtime failures when Puma/Rails tries to write pid/cache files under tmp/. Consider adding an entrypoint that chowns /rails/tmp at container start (then drops privileges), or adjust the volume/user strategy so /rails/tmp is writable by the rails user.