content: align shrinkflation series posts #2-5 frontmatter and nav links

Update frontmatter and footer navigation for dairy, frozen food,
household essentials, and snacks posts to match the cereal post series
format. Sets consistent series name "The Shrinkflation Files", correct
part numbers (2–5), and properly linked prev/next nav footers.

Refs: CAR-157, CAR-114

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

content/marketing/blog/shrinkflation-dairy-eggs-2026.md

@@ -1,13 +1,13 @@
 ---
-title: "Shrinkflation Report: The Incredible Cost of Eggs, Milk, and Yogurt in 2026"
+title: "The Shrinkflation Files: Dairy and Eggs"
 slug: shrinkflation-dairy-eggs-2026
-date: 2026-04-15
-author: CartSnitch Team
-category: Shrinkflation Report
-tags: [shrinkflation, dairy, eggs, milk, yogurt, grocery prices]
 status: draft
-series: shrinkflation-case-studies
+version: 1.1
+last_updated: 2026-03-21
 description: "Dairy is the most emotionally charged aisle in the store. Egg prices swing wildly, yogurt containers keep shrinking, and milk pricing defies logic. We tracked the numbers."
+tags: ["shrinkflation", "dairy", "eggs", "grocery-prices", "data"]
+series: "The Shrinkflation Files"
+series_part: 2
 ---
 
 # Shrinkflation Report: The Incredible Cost of Eggs, Milk, and Yogurt in 2026
@@ -95,4 +95,4 @@ The data is clear. The question is whether consumers have access to it. That's w
 
 ---
 
-*This is the third in a series of CartSnitch Shrinkflation Reports. Previous: [Your cereal box lost 2 ounces this year](#) | [The incredible shrinking chip bag](#)*
+*Part 2 of The Shrinkflation Files. [Part 1: Cereal](/blog/shrinkflation-cereal-2026) | Up next: [Part 3: Frozen Food](/blog/shrinkflation-frozen-food-2026)*

content/marketing/blog/shrinkflation-frozen-food-2026.md

@@ -1,13 +1,13 @@
 ---
-title: "Shrinkflation Report: Your Frozen Pizza Shrank and Your Ice Cream Did Too"
+title: "The Shrinkflation Files: Frozen Food"
 slug: shrinkflation-frozen-food-2026
-date: 2026-04-29
-author: CartSnitch Team
-category: Shrinkflation Report
-tags: [shrinkflation, frozen food, ice cream, frozen pizza, grocery prices]
 status: draft
-series: shrinkflation-case-studies
+version: 1.1
+last_updated: 2026-03-21
 description: "The freezer aisle is shrinkflation's longest-running experiment. Ice cream lost a quarter of its volume over 15 years. Frozen pizzas are lighter. And frozen dinners cost more per ounce than fresh ingredients."
+tags: ["shrinkflation", "frozen-food", "ice-cream", "grocery-prices", "data"]
+series: "The Shrinkflation Files"
+series_part: 3
 ---
 
 # Shrinkflation Report: Your Frozen Pizza Shrank and Your Ice Cream Did Too
@@ -103,4 +103,4 @@ That's the pattern playing out right now across frozen pizza, frozen meals, and
 
 ---
 
-*This is the fifth and final case study in our launch series of CartSnitch Shrinkflation Reports. Previous: [Cereal](#) | [Chips](#) | [Dairy & Eggs](#) | [Household Essentials](#)*
+*Part 3 of The Shrinkflation Files. [Part 2: Dairy and Eggs](/blog/shrinkflation-dairy-eggs-2026) | Up next: [Part 4: Household Essentials](/blog/shrinkflation-household-essentials-2026)*

content/marketing/blog/shrinkflation-household-essentials-2026.md

@@ -1,13 +1,13 @@
 ---
-title: "Shrinkflation Report: Fewer Sheets, Same Price — The Household Essentials Squeeze"
+title: "The Shrinkflation Files: Household Essentials"
 slug: shrinkflation-household-essentials-2026
-date: 2026-04-22
-author: CartSnitch Team
-category: Shrinkflation Report
-tags: [shrinkflation, household, paper towels, detergent, toilet paper, grocery prices]
 status: draft
-series: shrinkflation-case-studies
+version: 1.1
+last_updated: 2026-03-21
 description: "Toilet paper has fewer sheets. Detergent does fewer loads. Paper towels are thinner. We tracked the household essentials aisle and the numbers are stark."
+tags: ["shrinkflation", "household", "paper-towels", "detergent", "grocery-prices", "data"]
+series: "The Shrinkflation Files"
+series_part: 4
 ---
 
 # Shrinkflation Report: Fewer Sheets, Same Price — The Household Essentials Squeeze
@@ -99,4 +99,4 @@ But the data doesn't lie. And now you have it.
 
 ---
 
-*This is the fourth in a series of CartSnitch Shrinkflation Reports. Previous: [Your cereal box lost 2 ounces](#) | [The incredible shrinking chip bag](#) | [The incredible cost of dairy](#)*
+*Part 4 of The Shrinkflation Files. [Part 3: Frozen Food](/blog/shrinkflation-frozen-food-2026) | Up next: [Part 5: Snacks and Chips](/blog/shrinkflation-snacks-chips-2026)*

content/marketing/blog/shrinkflation-snacks-chips-2026.md

@@ -1,13 +1,13 @@
 ---
-title: "Shrinkflation Report: The Incredible Shrinking Chip Bag"
+title: "The Shrinkflation Files: Snacks and Chips"
 slug: shrinkflation-snacks-chips-2026
-date: 2026-04-08
-author: CartSnitch Team
-category: Shrinkflation Report
-tags: [shrinkflation, snacks, chips, grocery prices]
 status: draft
-series: shrinkflation-case-studies
-description: "Chip bags are bigger than ever — but the chips inside keep disappearing. We tracked package weights across 12 major snack brands."
+version: 1.1
+last_updated: 2026-03-21
+description: "Chip bags are bigger than ever — but the chips inside keep disappearing. We tracked package weights across 12 major snack brands and the numbers are stark."
+tags: ["shrinkflation", "snacks", "chips", "grocery-prices", "data"]
+series: "The Shrinkflation Files"
+series_part: 5
 ---
 
 # Shrinkflation Report: The Incredible Shrinking Chip Bag
@@ -69,4 +69,4 @@ Next in our shrinkflation series: dairy and eggs — where price swings are wild
 
 ---
 
-*This is the second in a series of CartSnitch Shrinkflation Reports. See also: [Your cereal box lost 2 ounces this year](#).*
+*Part 5 of The Shrinkflation Files. [Part 4: Household Essentials](/blog/shrinkflation-household-essentials-2026) | [Start from the beginning: Part 1, Cereal](/blog/shrinkflation-cereal-2026)*