Add devcontainer + Copilot instructions

[gn00295120]

• devcontainer.json — one-click Codespaces setup
• .github/copilot-instructions.md — project-specific Copilot context

[Copilot]

Pull request overview

Adds developer-experience scaffolding for this repository (Codespaces/devcontainer setup plus Copilot context) to make onboarding and local development more consistent with the project’s Python + MCP server workflow.

Changes:

• Add .devcontainer/devcontainer.json for a one-click containerized Python dev environment.
• Add .github/copilot-instructions.md to provide project-specific Copilot guidance (NotebookLM + Claude + MCP tools, testing/style expectations).

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
.github/copilot-instructions.md	Adds Copilot context about the project and expected coding/testing practices.
.devcontainer/devcontainer.json	Defines a devcontainer image, post-create dependency installation, and recommended VS Code extensions.

[Copilot]

The Copilot instructions say to “Follow PEP 8”, but the repo’s enforced style is Ruff with line-length = 120 and E501 ignored (so it does not strictly follow PEP 8 line-length rules). To avoid misleading guidance, consider updating this to reference the actual Ruff configuration (and/or the 120-char line length) rather than generic PEP 8.

Suggested change

	This is a Python project that integrates Google NotebookLM with Claude for content generation. It provides 13 MCP tools. Follow PEP 8, use type hints, and write pytest-compatible tests.
	This is a Python project that integrates Google NotebookLM with Claude for content generation. It provides 13 MCP tools. Follow the Ruff configuration (120-character line length; generally PEP 8-aligned with E501 disabled), use type hints, and write pytest-compatible tests.

[Copilot]

postCreateCommand suppresses errors (2>/dev/null) and then unconditionally succeeds (|| true). This can leave a Codespace/devcontainer in a broken state with missing dependencies (and the fallback pip install -r requirements.txt also skips dev deps like pytest/ruff). Consider removing the stderr suppression and the final || true so failures are visible, and (if you want the container to be usable for auth flows) optionally add a step to install Playwright browsers (e.g., Chromium) as documented in the repo setup guide.

Suggested change

	"postCreateCommand": "pip install -e \".[dev]\" 2>/dev/null || pip install -r requirements.txt 2>/dev/null || true",
	"customizations": {
	"vscode": {
	"postCreateCommand": "pip install -e \".[dev]\" || pip install -r requirements.txt",
	"customizations": {
	"vscode": {