fix(CDPBrowser): narrow cssProps payload, correct seeInField boolean semantics, regenerate docs

- cdpBrowserClient.js: cssProps now reads only the requested properties
  (mirroring the attrsMap pattern) instead of serializing the entire
  ~1090-key/~35KB computed style object per element. CDPBrowser.js's
  grabCssPropertyFrom(All)/seeCssPropertiesOnElements now pass the
  camelCase-resolved property names through the payload.

- _seeInField's boolean branch asserted field *existence*
  (values.length > 0) instead of checkbox *checked state*, so
  I.seeInField(locator, false) silently passed as long as the field
  existed, regardless of whether it was checked. Now asserts the
  checkbox's checked state via the existing 'checked' client action,
  mirroring Puppeteer's proceedSeeInField boolean semantics: true passes
  iff checked, false passes iff unchecked. No webapi.js test currently
  exercises seeInField/dontSeeInField with a boolean value, so this does
  not change either covering suite's tallies.

- waitForCookie passed a literal 'placeholder' message to _poll and
  rewrote it in a catch block that also swallowed any real transport
  error from _poll/grabCookies. Now passes the real timeout message
  directly and the try/catch is gone.

- Regenerated docs/helpers/CDPBrowser.md (npm run docs), which was still
  missing all ~40 methods added when CDPBrowser was wired to the shared
  webapi.js spec. Obscura.md/Kitesurf.md are unchanged (they only document
  methods declared directly on those classes).

Chrome: 185 passing / 128 pending / 0 failing (unchanged).
Obscura: 108 passing / 193 pending / 0 failing (unchanged).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: DavertMik