chore: add changeset and release notes for reverse callee index

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: prosdev

.changeset/reverse-callee-index.md

@@ -0,0 +1,5 @@
+---
+"@prosdevlab/dev-agent": patch
+---
+
+Add reverse callee index to dev_refs — callers now work. Previously "No callers found" for every function because caller detection relied on semantic search (returned similar concepts, not call sites). Now uses a persisted reverse index with 4,000+ caller entries, compound keys for O(1) lookup, and class-level aggregation.

website/content/latest-version.ts

@@ -4,10 +4,10 @@
  */
 
 export const latestVersion = {
-  version: '0.12.1',
-  title: 'Cleaner Search Output + refs Fix',
-  date: 'April 1, 2026',
+  version: '0.12.2',
+  title: 'Reverse Callee Index for dev_refs',
+  date: 'April 2, 2026',
   summary:
-    'MCP search results drop misleading scores, add result preamble, and fix dev_refs silently returning no results.',
-  link: '/updates#v0121--cleaner-search-output--refs-fix',
+    'dev_refs callers finally work — reverse callee index with 4,000+ entries, compound keys, class aggregation, and O(1) lookups.',
+  link: '/updates#v0122--reverse-callee-index-for-dev_refs',
 } as const;

website/content/updates/index.mdx

@@ -9,6 +9,22 @@ What's new in dev-agent. We ship improvements regularly to help AI assistants un
 
 ---
 
+## v0.12.2 — Reverse Callee Index for dev_refs
+
+*April 2, 2026*
+
+**`dev_refs` callers finally work.**
+
+- **Reverse callee index:** maps callee names to their callers, built at index time from scan data. 4,000+ caller entries on a typical codebase
+- **Compound keys:** `file:name` for TypeScript (O(1) exact match), bare names for Go/Rust/Python with secondary name index for O(1) resolution
+- **Single artifact:** persisted inside `dependency-graph.json` v2 — atomic write, no drift between graph and reverse index
+- **Class aggregation:** `dev refs "SearchAdapter"` aggregates callers across constructor + all methods
+- **Backward compatible:** v1 graph files load fine, callers return empty until re-indexed
+- Before: `dev refs "validateArgs"` → "No callers found"
+- After: `dev refs "validateArgs"` → 5 adapter callers listed with file paths and line numbers
+
+---
+
 ## v0.12.1 — Cleaner Search Output + refs Fix
 
 *April 1, 2026*