Surface pending review queues on admin home

[maebeale]

Closes #1524

What is the goal of this PR and why is this important?

• When an admin logs in and lands on the admin home (/admin), there was no way to see what's waiting for them without visiting each ideas index individually.
• This surfaces a single notification banner summarizing all the admin review queues — user-submitted ideas that haven't yet been promoted into their published counterparts.
• Makes the review backlog visible at a glance, which is the core stakeholder ask in the issue.

How did you approach the change?

• Added a pending_review scope to each idea model — an idea is "pending" until it has been promoted:
  • StoryIdea — no associated Story (where.missing(:stories))
  • WorkshopVariationIdea — no associated WorkshopVariation
  • WorkshopIdea — no associated Workshop
• Added a PendingReviewSummary service that gathers each queue's label, pending count, and originating model, plus pending_queues / total_count / any? helpers.
• Admin::HomeController#index builds the summary; a new _review_notifications partial renders a dismissible-style yellow banner at the top of the dashboard with a count badge per queue, each linking to the relevant index. The banner is omitted entirely when nothing is pending.
• Extensible by design: adding a new review queue is a one-line addition to QUEUE_DEFINITIONS.

UI Testing Checklist

• As an admin with pending story / workshop variation / workshop ideas, the banner shows on /admin with correct counts and links.
• As an admin with everything promoted, the banner does not render.
• Count badges link to the corresponding ideas index.

Anything else to add?

• Tests: model scope specs, a PendingReviewSummary service spec, and request specs asserting the banner appears (and is omitted when nothing is pending). All passing.
• Banner uses the existing flash/notification yellow palette and the dashboard's rounded-xl shadow card styling for visual consistency.
• Counts link to each full index (which already shows promotion status); a future enhancement could add a "pending only" filter to those indexes.

🤖 Generated with Claude Code

[maebeale]

Adding a new admin review queue is intentionally a one-line change here — append { model: SomeIdea, label: "..." } and it shows up on the dashboard automatically, provided the model defines a pending_review scope.

[maebeale]

"Pending review" is derived from the existing promotion relationship rather than a new status column: an idea is pending until it has been promoted into a Story (the same signal the index's "Promoted to Story" column already uses). Keeps this consistent with how the rest of the app reasons about idea state and avoids a migration.

[maebeale]

Banner renders above the existing cards so the backlog is the first thing an admin sees on login. The partial no-ops when nothing is pending, so the dashboard is unchanged when caught up.

[Copilot]

Pull request overview

Surfaces a consolidated “pending review” summary on the admin dashboard (/admin) so admins can see (and navigate to) unpromoted idea queues at a glance.

Changes:

• Added pending_review scopes to idea models based on whether a promoted counterpart exists.
• Introduced PendingReviewSummary service to aggregate queue labels + counts for the dashboard.
• Rendered a new admin-home notification banner and added request/service/model specs to cover the behavior.

Reviewed changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
app/models/story_idea.rb	Adds pending_review scope using where.missing(:stories) to identify unpromoted story ideas.
app/models/workshop_variation_idea.rb	Adds pending_review scope using where.missing(:workshop_variations) to identify unpromoted variation ideas.
app/models/workshop_idea.rb	Adds pending_review scope using where.missing(:workshops) to identify unpromoted workshop ideas.
app/services/pending_review_summary.rb	New service that enumerates queue definitions and computes per-queue + total pending counts.
app/controllers/admin/home_controller.rb	Instantiates PendingReviewSummary for use by the admin home view.
app/views/admin/home/index.html.erb	Renders the new review notification partial on the admin dashboard.
app/views/admin/home/_review_notifications.html.erb	New banner partial showing total pending count and per-queue links.
spec/services/pending_review_summary_spec.rb	Adds service specs for queue counts, filtering pending queues, and totals.
spec/requests/admin/home_spec.rb	Adds request specs asserting the banner appears/omits based on pending items.
spec/models/story_idea_spec.rb	Adds model scope specs for StoryIdea.pending_review.
spec/models/workshop_variation_idea_spec.rb	Adds model scope specs for WorkshopVariationIdea.pending_review.
spec/models/workshop_idea_spec.rb	Adds model scope specs for WorkshopIdea.pending_review.
AGENTS.md	Updates service count and documents PendingReviewSummary.