fix: improve Chromium fingerprint injection consistency

[Kernalsmelly]

Summary

• stop injecting generated accept-language through extra HTTP headers and pass the generated language through Playwright's native locale option instead
• default helper-generated Chromium fingerprints to HTTP/1-style headers and add matching Chromium client hints when needed
• make request-header filtering case-insensitive for HTTP/1 header casing
• apply existing headless Chromium fixes after user-agent spoofing, hide configurable navigator.webdriver, and avoid injecting hidden-frame-sized top-level window dimensions

Why

Issue #178 tracks Chrome fingerprints becoming detectable as headless after injection. The live areyouheadless check is especially sensitive to Playwright extra HTTP headers: native locale still sends Accept-Language, but injecting the same value through extraHTTPHeaders flips the detector to headless. This keeps locale consistency while avoiding that extra-header signal, then covers other mismatches observed while reproducing the issue.

Verification

• pnpm exec vitest run test/fingerprint-injector/fingerprint-injector.test.ts -t "filters request headers|native locale|defaults Chromium|applies headless Chromium fixes"
• pnpm --filter generative-bayesian-network compile; pnpm --filter header-generator compile; pnpm --filter fingerprint-generator compile; pnpm --filter fingerprint-injector compile
• pnpm exec prettier packages/fingerprint-injector/src/fingerprint-injector.ts packages/fingerprint-injector/src/utils.js test/fingerprint-injector/fingerprint-injector.test.ts --check
• live https://arh.antoinevastel.com/bots/areyouheadless checks returned You are not Chrome headless for:
  • Playwright headless Chromium with a Windows Chrome fingerprint
  • Playwright headless Chromium with a Linux Chrome fingerprint
  • Puppeteer headless Chrome with a Windows Chrome fingerprint

Fixes #178

@algora-pbc /claim #178

[Kernalsmelly]

@algora-pbc /claim #178