Add Playground page for Lightpanda Cloud

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• Add a new Playground page documenting the console script editor, the CDP_WS_URL connection variable, the preinstalled CDP clients, and the run limits
• Link to it from Getting started, where it sits alongside the HTTP API and MCP as another way to use the cloud
• Note on Puppeteer and Playwright that the playground exposes CDP_WS_URL instead of LPD_TOKEN
• State on Limits and billing that browser hours and concurrency apply to every session, however it was opened

Note

This branch is stacked on #75 (complete-cloud-section), which is not merged yet. The base of this PR is complete-cloud-section rather than main, so the diff shows only the playground commits. It needs to be retargeted to main once #75 lands, which GitHub does automatically if the complete-cloud-section branch is deleted on merge.

Preview. The marketing site pins apps/docs as a submodule, so each PR gets its own preview branch there:

Branch on the site	Points at	Shows
docs-playground	playground	this PR, on top of #75
complete-cloud-section	complete-cloud-section	#75 alone

Because the branches are stacked, the docs-playground preview necessarily includes the #75 changes as well.

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Claude flagged this while writing the page.

The playground Settings panel shows node:24.18-bookworm-slim (webapp, src/components/pages/playground/scripts/PlaygroundScriptSidebar.tsx:13). That is only the build stage of the runtime image, blade/docker/Dockerfile.runtime:3. Scripts run on the final stage, gcr.io/distroless/nodejs22-debian12:nonroot (line 15), whose entrypoint is that image's own node binary (line 34). Only node_modules is copied out of the build stage (line 30). The image label agrees: io.lightpanda.blade.node.version="22" (line 18).
It looks like this came from blade 65abc4d ("chore: update node to lts 24.18"), which bumped the build stage from node:22-bookworm-slim to 24.18 and left the final stage and the label on 22. So the runtime is still Node 22 while the UI advertises 24.

I left the Node version out of the page until this is settled.