profiling.sampling flamegraph does not escape function names in HTML output #153840

Bug description

The flamegraph exporter in profiling.sampling embeds profile strings into the generated HTML without escaping:

1. _create_flamegraph_html writes json.dumps(data) into an inline <script> block. A function name containing </script> breaks out of the script element.

2. flamegraph.js interpolates the raw function name into a tooltip via .html() (innerHTML).

The sibling heatmap exporter already escapes its embedded data (html.escape(json.dumps(...))), and flamegraph.js already defines and uses escapeHtml() for displayName and source lines -- the function name was missed.

As a bonus, <lambda>, <module>, <genexpr> currently render as empty tooltip titles because the browser drops them as unknown tags. Escaping fixes this.

CPython versions tested on

main

Operating systems tested on

macOS

Linked PRs

• gh-153840: Escape special characters in flamegraph function names #153841