perf(memory): release old navigation request in NetworkCollector

[flobo3]

Issue #1192

Problem

In --autoConnect mode, chrome-devtools-mcp experiences a severe memory leak (~13 MB/min) when Chrome is actively used. This eventually leads to OOM crashes or kernel panics.

The root cause is in src/PageCollector.ts:

1. NetworkCollector overrides splitAfterNavigation but forgets to call navigations.splice(this.#maxNavigationSaved), causing the array of navigations to grow infinitely.
2. Even within a single navigation (e.g., in long-lived SPA applications), the navigations[0] array grows infinitely because there is no limit on the number of items collected per navigation. Since HTTPRequest objects are heavy, this quickly exhausts memory.

Solution

1. Changed #maxNavigationSaved to protected maxNavigationSaved so subclasses can access it.
2. Added navigations.splice(this.maxNavigationSaved) to NetworkCollector.splitAfterNavigation to ensure old navigations are properly discarded.
3. Introduced protected maxItemsPerNavigation = 5000 to limit the number of items stored per navigation. When the limit is reached, the oldest item is removed (shift()), preventing unbounded memory growth in SPAs.

Tested locally by running npm run build and verifying the fix.

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[wolfib]

Thank you!

Adding the missing splice(..) to the NetworkCollector LGTM. I'm not so sure about the maxItemsPerNavigation change, is it possible that this throws away data we actually want to keep? Here are my suggestions:

• Create a separate PRe for the introduction of maxItemsPerNavigation.
• In this PR, add a test to PageCollector.test.ts which verifies that NetworkCollector doesn't grow beyond maxNavigationSaved
• Ensure that package-lock.json is not changed (npm ci instead of npm i might help).

[flobo3]

Thanks for the review!

I have updated the PR according to your suggestions:

1. Reverted the maxItemsPerNavigation change (I will create a separate PR for it).
2. Added navigations.splice(3) to NetworkCollector (hardcoded to 3 to match the private #maxNavigationSaved in the base class).
3. Added a test in PageCollector.test.ts to verify that NetworkCollector doesn't grow beyond maxNavigationSaved.
4. Reverted package-lock.json changes.

Let me know if anything else is needed!

[wolfib]

Thanks! Just 1 more nit: could you please go back to maxNavigationSaved being protected instead of hardcoding it in the derived class?

[flobo3]

Done! Changed #maxNavigationSaved to protected maxNavigationSaved and updated the derived class to use it instead of the hardcoded value.

[wolfib]

Cool! Now only the test needs fixing.

[flobo3]

Done! I've reverted the + 1 back to this.maxNavigationSaved in both places and updated the test to expect 3 navigations instead of 4. Thanks for the clarification!

[Lightning00Blade]

LGTM, thanks!