Replace migration-template.md with breaking-change-template.md (#2931)

Author: pwizla

agents/templates/INDEX.md

@@ -22,6 +22,6 @@ This non-docs index lists the canonical authoring templates for CMS documentatio
 - Purpose: Lightweight API page skeleton covering endpoints, auth, parameters, and example requests/responses.
 - Path: `agents/templates/api-template.md`
 
-## Migration Template
-- Purpose: Migration/breaking‑change format with impact, before/after, and a numbered migration sequence.
-- Path: `agents/templates/migration-template.md`
+## Breaking Change Template
+- Purpose: Individual breaking change page with BreakingChangeIdCard, side-by-side v4/v5 comparison, and migration notes with manual procedure.
+- Path: `agents/templates/breaking-change-template.md`

agents/templates/breaking-change-template.md

@@ -0,0 +1,120 @@
+---
+title: TITLE — Clear statement of the change
+description: One sentence explaining what changed and who is affected.
+sidebar_label: Short label (optional)
+displayed_sidebar: cmsSidebar
+tags:
+ - breaking changes
+ - TOPIC_TAG
+ - upgrade to Strapi 5
+---
+
+<!--
+================================================================================
+BREAKING CHANGE TEMPLATE
+================================================================================
+Use this template for individual breaking change pages in /cms/migration/vX-to-vY/breaking-changes/
+
+QUICK REFERENCE - BreakingChangeIdCard props:
+  plugins            → Add if this breaking change affects plugin developers
+  codemod            → Add if FULLY handled by a codemod
+  codemodPartly      → Add if PARTLY handled by a codemod
+  codemodName="..."  → Codemod identifier (e.g., "entity-service-document-service")
+  codemodLink="..."  → GitHub URL to the codemod source code
+  info="..."         → Additional note (e.g., "handled by data migration script")
+
+EXAMPLES:
+  <BreakingChangeIdCard />                                    → No plugins, no codemod
+  <BreakingChangeIdCard plugins />                            → Affects plugins, no codemod
+  <BreakingChangeIdCard plugins codemod />                    → Affects plugins, fully automated
+  <BreakingChangeIdCard plugins codemodPartly                 → Affects plugins, partly automated
+    codemodName="my-codemod"
+    codemodLink="https://github.com/strapi/strapi/blob/develop/..." />
+================================================================================
+-->
+
+import Intro from '/docs/snippets/breaking-change-page-intro.md'
+import MigrationIntro from '/docs/snippets/breaking-change-page-migration-intro.md'
+
+# TITLE — Can expand on frontmatter title
+
+Brief 1-2 sentence introduction explaining the change in context.
+
+<Intro />
+
+<BreakingChangeIdCard />
+
+## Breaking change description
+
+<SideBySideContainer>
+
+<SideBySideColumn>
+
+**In Strapi v4**
+
+Description of v4 behavior.
+
+```js
+// v4 code example (if applicable)
+```
+
+</SideBySideColumn>
+
+<SideBySideColumn>
+
+**In Strapi 5**
+
+Description of v5 behavior.
+
+```js
+// v5 code example (if applicable)
+```
+
+</SideBySideColumn>
+
+</SideBySideContainer>
+
+## Migration
+
+<MigrationIntro />
+
+### Notes
+
+- Key information about the change.
+- Link to related documentation: see [Feature name](/cms/path/to/doc).
+- Link to related breaking change: see [related entry](/cms/migration/v4-to-v5/breaking-changes/slug).
+
+### Manual procedure
+
+Describe manual steps if needed. Use one of these formats:
+
+**Simple prose:** No manual migration is required.
+
+**Numbered steps:**
+1. First action
+2. Second action
+3. Verify the change
+
+**Before/After code:**
+
+<SideBySideContainer>
+<SideBySideColumn>
+
+**In Strapi v4**
+
+```js
+// Old code
+```
+
+</SideBySideColumn>
+
+<SideBySideColumn>
+
+**In Strapi 5**
+
+```js
+// New code
+```
+
+</SideBySideColumn>
+</SideBySideContainer>