feat(marketplace): add lean/full profile switching for token optimization

- Add marketplace-lean.json (6 plugins) and marketplace-full.json (12 plugins)
- Add .mcp-lean.json (gitea only) and .mcp-full.json (5 servers)
- Create scripts/switch-profile.sh for easy profile switching
- Update sprint-status.md with conditional skill loading
- Set lean profile as default (~14k token savings)

Lean profile includes: projman, git-flow, pr-review, clarity-assist,
code-sentinel, doc-guardian

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.mcp-lean.json

@@ -0,0 +1,8 @@
+{
+  "mcpServers": {
+    "gitea": {
+      "command": "./mcp-servers/gitea/run.sh",
+      "args": []
+    }
+  }
+}