McpContext currently assumes that there is a page. Eventually we might
support closing the browser by closing the last page but right now we do
not really have responses that indicate that the browser was closed. So
this PR helps the LLM understand that it is okay to keep the last page
running (and there are platform-specific differences as to what happens
if the last page is closed).
Ref https://github.com/ChromeDevTools/chrome-devtools-mcp/issues/87
* add script `npm run docs` that builds, generate docs and runs
formatter to auto fix formatting after doc generation
* rename generate-docs to docs:generate
* update presubmit workflow
* add docs process to contributing.md
Alex Rudenko