Add missing CommitmentDriftSummarizer model, dashboard summary stats, and feed pagination

CommitmentDriftSummarizer was referenced by SourceDocumentProcessorJob but
never committed, causing NameError in production. Also adds commitment
status summary counts to the dashboard API and total_count to feed items
pagination metadata.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: xrendan

app/controllers/api/dashboard_controller.rb

@@ -45,9 +45,25 @@ def at_a_glance
         }
       end
 
+      all_commitments = government.commitments
+      total = all_commitments.count
+      status_counts = all_commitments.group(:status).count
+
+      not_started = status_counts.fetch("not_started", 0)
+      implemented = status_counts.fetch("implemented", 0)
+      in_progress = status_counts.fetch("in_progress", 0) +
+                    status_counts.fetch("partially_implemented", 0)
+      successful = all_commitments.joins(:success_criteria).merge(Criterion.where(status: :met)).distinct.count
+
       render json: {
         government: { id: government.id, name: government.name },
-        total_commitments: government.commitments.count,
+        total_commitments: total,
+        summary: {
+          not_started: { count: not_started, label: "Not Started", subtitle: "no action taken" },
+          completed: { count: implemented, label: "Completed", subtitle: "of #{total} commitments" },
+          successful: { count: successful, label: "Successful", subtitle: "meeting success criteria" }
+        },
+        status_counts: status_counts,
         policy_areas: data
       }
     end

app/controllers/feed_items_controller.rb

@@ -2,15 +2,16 @@ class FeedItemsController < ApplicationController
   def index
     scope = params[:commitment_id] ? FeedItem.where(commitment_id: params[:commitment_id]) : FeedItem.all
 
-    @feed_items = scope
+    @filtered = scope
       .newest_first
       .by_event_type(params[:event_type])
       .by_policy_area(params[:policy_area_id])
       .since(params[:since])
       .until_date(params[:until])
       .includes(:commitment, :policy_area)
 
-    @feed_items = @feed_items.limit(page_size).offset(page_offset)
+    @total_count = @filtered.count
+    @feed_items = @filtered.limit(page_size).offset(page_offset)
 
     respond_to do |format|
       format.json { render json: feed_items_json }
@@ -20,18 +21,22 @@ def index
 
   private
 
+  def current_page
+    [(params[:page] || 1).to_i, 1].max
+  end
+
   def page_size
     [(params[:per_page] || 50).to_i, 100].min
   end
 
   def page_offset
-    [(params[:page] || 1).to_i - 1, 0].max * page_size
+    (current_page - 1) * page_size
   end
 
   def feed_items_json
     {
       feed_items: @feed_items.map { |fi| serialize_feed_item(fi) },
-      meta: { page: (params[:page] || 1).to_i, per_page: page_size }
+      meta: { page: current_page, per_page: page_size, total_count: @total_count }
     }
   end
 

app/models/commitment_drift_summarizer.rb

@@ -0,0 +1,36 @@
+class CommitmentDriftSummarizer < Chat
+  include Structify::Model
+
+  MODEL = "gemini-3.1-flash-lite-preview"
+
+  after_create { with_model(MODEL, provider: :gemini, assume_exists: true) }
+
+  schema_definition do
+    version 1
+    name "CommitmentDriftSummarizer"
+    field :change_summary, :string,
+      description: "A 1-3 sentence human-readable summary of what changed and why it matters"
+  end
+
+  def system_prompt
+    "You are a government policy analyst summarizing changes to official commitments. " \
+      "Be concise and factual. Focus on what changed and its significance."
+  end
+
+  def prompt(old_values, new_values)
+    <<~PROMPT
+      A government commitment has been updated in a new source document.
+      Summarize what changed and why it matters in 1-3 sentences.
+
+      PREVIOUS VERSION:
+      Title: #{old_values[:title]}
+      Description: #{old_values[:description]}
+      Original text: #{old_values[:original_text]}
+
+      NEW VERSION:
+      Title: #{new_values[:title]}
+      Description: #{new_values[:description]}
+      Original text: #{new_values[:original_text]}
+    PROMPT
+  end
+end