New features suggested by Claude after we needed `Emulation.setTimezoneOverride`

[simonw]

Edited to the ones I like the sound of:

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Feature: User agent override
CDP Command: Emulation.setUserAgentOverride
Example CLI: rodney ua "Googlebot/2.1"
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Feature: Timezone override
CDP Command: Emulation.setTimezoneOverride
Example CLI: rodney timezone "Asia/Tokyo" (no restart needed!)
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Feature: Locale override
CDP Command: Emulation.setLocaleOverride
Example CLI: rodney locale "de-DE"
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Feature: Geolocation spoofing
CDP Command: Emulation.setGeolocationOverride
Example CLI: rodney geo --lat 48.86 --lon 2.35
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Feature: Emulate media
CDP Command: Emulation.setEmulatedMedia
Example CLI: rodney media --feature prefers-color-scheme=dark
Medium Priority — Great for Specific Testing
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Feature: CPU throttling
CDP Command: Emulation.setCPUThrottlingRate
Use Case: Simulate slow devices
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Feature: Vision deficiency
CDP Command: Emulation.setEmulatedVisionDeficiency
Use Case: Accessibility screenshots (deuteranopia, blurred vision, etc.)
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Feature: Hide scrollbars
CDP Command: Emulation.setScrollbarsHidden
Use Case: Cleaner screenshots
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Feature: Disable JavaScript
CDP Command: Emulation.setScriptExecutionDisabled
Use Case: Test progressive enhancement
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Feature: Inject script on load
CDP Command: Page.addScriptToEvaluateOnNewDocument
Use Case: Override navigator.webdriver, inject polyfills
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Feature: Mock API responses
CDP Command: Fetch.fulfillRequest
Use Case: Return synthetic responses without a backend