feat: add Playwright text selector support and use TIMING constants

[konard]

Summary

This PR adopts improvements from https://github.com/konard/hh-job-application-automation (as requested in #7):

• Add Playwright text selector support: New functions isPlaywrightTextSelector() and parsePlaywrightTextSelector() to properly handle Playwright's :has-text() and :text-is() pseudo-selectors
• Update normalizeSelector(): Now converts Playwright text selectors to valid CSS selectors for browser context operations
• Update withTextSelectorSupport(): Extended to handle Playwright text selectors in addition to Puppeteer text selector objects
• Use TIMING constants: Added NAVIGATION_TIMEOUT constant and updated navigation-manager to use it instead of hardcoded values

Why These Changes

The upstream hh-job-application-automation repository has battle-tested improvements for handling Playwright's text pseudo-selectors. These selectors (:has-text(), :text-is()) are valid for Playwright's locator API but not for document.querySelectorAll. The changes properly normalize these selectors to valid CSS selectors by:

1. Detecting Playwright text selectors in string format
2. Parsing out the base selector and text content
3. Using page.evaluate() to find matching elements
4. Generating unique CSS selectors (using data-qa attribute or nth-of-type)

Test Plan

• All 337 unit tests pass
• ESLint passes with no errors
• Prettier formatting check passes
• Pre-commit hooks pass

Fixes #7

🤖 Generated with Claude Code

[konard]

🤖 Solution Draft Log

This log file contains the complete execution trace of the AI solution draft process.

💰 Cost estimation:

• Public pricing estimate: $6.048846 USD
• Calculated by Anthropic: $3.805937 USD
• Difference: $-2.242909 (-37.08%)
  📎 Log file uploaded as GitHub Gist (790KB)
  🔗 View complete solution draft log

---

Now working session is ended, feel free to review and add any feedback on the solution draft.