Add GitHub Codespaces support with CI validation

[Copilot]

No devcontainer configuration existed, requiring a full local Frappe bench setup to contribute. Adds first-class Codespaces support and a CI workflow to validate the config on PRs without merging.

Devcontainer (.devcontainer/)

• devcontainer.json – attaches VS Code to the frappe service; forwards ports 8000 (Frappe) and 8080 (Vite); installs Python, Vue/Volar, ESLint, Tailwind, Prettier, GitLens extensions; points the Python interpreter at the bench virtualenv
• docker-compose.yml – mariadb:10.6 + redis:alpine + frappe/bench:latest; repo mounted at /workspace; bench installation persisted in a named volume so container rebuilds don't re-run setup
• setup.sh – idempotent post-create script: waits for MariaDB, runs bench init, symlinks /workspace as the live app (edits reflected immediately), creates gameplan.localhost, installs frontend deps via pnpm install

After the Codespace opens

# Terminal 1
cd ~/frappe-bench && bench start      # http://localhost:8000

# Terminal 2
cd /workspace && pnpm dev             # http://localhost:8080/g
# Login: alex@example.com / 123

CI validation (.github/workflows/devcontainer.yml)

Triggers on PRs/pushes that touch .devcontainer/**. Uses devcontainers/ci@v0.3 to build the full Docker Compose stack and run setup.sh inside the container.

setup.sh detects CI=true (set automatically by GitHub Actions) and takes a fast path — installs pnpm, prints tool versions, exits — instead of the full 10–15 min bench init. Proves the image builds, services start, and required tooling is present in a few minutes.

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✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.

[cypress]

gameplan    Run #406

Run Properties:   Passed #406  •  36dfdb886d ℹ️: Merge b794560ebdf2c8c26e237fb8748feec4173b6548 into 7ab03f2d4c5ac04b2d26db9107f5...

Project	gameplan
Branch Review	copilot/setup-github-codespaces
Run status	Passed #406
Run duration	00m 48s
Commit	36dfdb886d ℹ️: Merge b794560ebdf2c8c26e237fb8748feec4173b6548 into 7ab03f2d4c5ac04b2d26db9107f5...
Committer	Copilot
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