chore: add changeset for git analytics removal

Author: prosdev

.changeset/remove-git-analytics.md

@@ -0,0 +1,36 @@
+---
+"@lytics/dev-agent-cli": minor
+"@lytics/dev-agent-core": patch
+"@lytics/dev-agent": patch
+---
+
+Remove git analytics commands to refocus on semantic value
+
+**BREAKING CHANGES:**
+
+- Remove `dev owners` command - use `git log` or GitHub contributors instead
+- Remove `dev activity` command - use `git log --since` for activity analysis
+
+**What's Changed:**
+
+- Removed 891 lines from `dev owners` command
+- Removed 175 lines from `dev activity` command  
+- Cleaned up dead code in `change-frequency.ts` (calculateFileAuthorContributions)
+- Simplified metrics collection to focus on code structure introspection
+
+**What's Kept:**
+
+- `code_metadata` table for debugging/introspection of indexed code
+- `calculateChangeFrequency` for `dev_map` MCP tool (shows commit activity in codebase structure)
+
+**Why:**
+
+Dev-agent's unique value is semantic search (embeddings + AST), not git analytics which GitHub/git already provide. This change reduces complexity by ~1,200 lines and refocuses on MCP tools for AI context.
+
+**Migration:**
+
+For contributor/ownership analytics, use:
+- `git log --format="%ae" <path> | sort | uniq -c | sort -rn` for ownership
+- `git log --since="1 month" --name-only | sort | uniq -c | sort -rn` for activity
+- GitHub's Contributors page for visualization
+