feat(identity): Agent GitHub Identity via GitHub Apps

[sabbour]

Agent GitHub Identity via GitHub Apps

Summary

Gives each Squad agent a distinct GitHub App identity so commits, PRs, and comments are attributed to the correct role (e.g., sabbour-squad-lead[bot]). Uses GitHub Apps for per-agent authentication rather than shared tokens.

Role Avatars

Each role gets a unique avatar for visual identification in GitHub activity:

Lead	Frontend	Backend	Tester

DevOps	Docs	Security	Data

Token Resolution — Standalone Script

Token resolution uses .squad/scripts/resolve-token.mjs, a self-contained script shipped by squad init / squad upgrade. It requires no npm dependency — only Node.js built-in modules (node:fs, node:path, node:crypto). Spawned agents call:

TOKEN=$(node .squad/scripts/resolve-token.mjs 'lead')

Key Files Changed

• templates/scripts/resolve-token.mjs — standalone token resolution script (new)
• packages/squad-cli/src/cli/core/templates.ts — manifest entry to ship the script
• packages/squad-sdk/src/config/init.ts — creates scripts/ dir during init
• templates/squad.agent.md.template — agent prompt with identity block
• packages/squad-cli/src/cli/commands/identity.ts — identity create/import/status CLI
• packages/squad-cli/src/cli/shell/spawn.ts — token injection during agent spawn
• docs/proposals/agent-github-identity.md — full design proposal
• .changeset/team-aware-identity-create.md — changeset for this feature

Branch Cleanup

This commit reverts unrelated .squad/ state changes (agent history files, decisions, decision inbox), avatar image additions, and package.json version bumps that had accumulated across prior commits. The PR diff now shows only identity feature changes.