chore(maestro): initial scaffold and brainstorm spec

Adds .claude/linear.json for Linear-driven skills (Maestro project on
team Naps62) and the brainstorm design doc covering architecture, wire
protocol, session model, auth, and prototype scope boundary.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.claude/linear.json

@@ -0,0 +1,12 @@
+{
+  "org": "naps62",
+  "team": "Naps62",
+  "project": "Maestro",
+  "defaultBranch": "main",
+  "commitScope": "maestro",
+  "remoteHost": "gitea",
+  "remoteBaseUrl": "https://git.naps.pt",
+  "contextFiles": ["CLAUDE.md"],
+  "prReviewers": [],
+  "labels": []
+}