feat: add optional stack traces to list_console_messages

[ZayanKhan-12]

What

Adds an opt-in includeStackTraces parameter to list_console_messages. When set, each listed message includes its resolved (source-mapped, ignore-list-filtered) stack trace — in the text output as indented frames under the message line, and in structuredContent as a pre-formatted stackTrace string, matching the format get_console_message already uses.

Why

Fixes the workflow described in #383: today the list output only contains plain message text, so an LLM debugging a page has to call get_console_message once per message to learn which file/function/line failed. With includeStackTraces: true the model can map every error to its source in a single call.

Design notes:

• Opt-in, default off — the default output is byte-for-byte unchanged, keeping the token cost of the common path identical.
• Reuses the existing DevTools stack resolution (createStackTraceForConsoleMessage / SymbolizedError) and the existing formatStackTrace formatting, so frames are source-mapped and ignore-listed exactly like in get_console_message.
• The per-message "1-based indexing" note is emitted once for the whole list instead of once per message to keep the output compact.
• Works for console API messages, uncaught errors (including Caused by: chains), and grouped repeated messages ([N times]).

Before / after

Default (unchanged):

## Console messages
Showing 1-1 of 1 (Page 1 of 1).
msgid=1 [log] Hello stack trace! (0 args)

With includeStackTraces: true:

## Console messages
Showing 1-1 of 1 (Page 1 of 1).
msgid=1 [log] Hello stack trace! (0 args)
  at foo (foo.ts:10:2)
  at bar (foo.ts:20:2)
  --- setTimeout -------------------------
  at schedule (util.ts:5:2)
Note: stack trace line and column numbers use 1-based indexing

structuredContent.consoleMessages[i] gains an optional "stackTrace": "at foo (foo.ts:10:2)\nat bar (foo.ts:20:2)\n..." field.

Relationship to #2060

Complements #2060 (source location for list_console_messages, issue #903): that PR surfaces the top-frame location for every message by default, while this one exposes the full stack trace behind an explicit opt-in. The features are independent and the changes are designed to coexist with minimal conflict.

Testing

• npm run build — passes
• npm run test:no-build — full suite passes (exit 0)
• npm run check-format — passes
• npm run gen — regenerated docs/tool-reference.md, CLI options, and tool-call metrics (included)

New coverage:

• tests/formatters/ConsoleFormatter.test.ts — snapshot tests for concise toString/toJSON with fetchStackTrace set (console message + uncaught error) and for the unchanged default.
• tests/tools/console.test.ts — integration tests asserting frames (at failingFn) appear in text and structuredContent when includeStackTraces: true, and are absent by default.

Fixes #383

🤖 Generated with Claude Code

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[OrKoN]

LGTM (this matches what we should in DevTools UI so generally could be useful to agents if there are not so many console messages).