fix: concurrency bugs, license, docs, and CI

[desperatee]

Summary

• Fix 2 HIGH-severity concurrency bugs found in code review (routeInjecting race, pipeTransport.Close race)
• Fix global logger mutation that caused log output corruption with multiple concurrent drivers
• Fix transformRunOptions mutating caller's shared *RunOptions in-place
• Fix Verbose default being silently lost when caller passes any RunOptions
• Add isolatedContext: true to all remaining evaluate methods
• Change LICENSE from MIT to Apache-2.0 (matching Patchright upstream)
• Add LLM-friendly usage guide with anti-detection best practices
• Add GitHub Actions CI workflow

Test plan

• All unit tests pass
• Integration test (driver install + browser launch) passes
• E2E test navigating walmart.ca with anti-detection config works
• go build ./... and go vet ./... clean
• navigator.webdriver returns false

Review findings addressed

#	Severity	Issue	Fix
1	HIGH	routeInjecting race on concurrent AddInitScript/ExposeBinding	atomic.Bool.CompareAndSwap
2	HIGH	Dead code in route handler (both branches identical)	Simplified to single Fallback call
3	HIGH	Global logger mutation across concurrent drivers	Driver reads d.options.Logger; package-level logger never mutated
4	HIGH	transformRunOptions mutates caller's *RunOptions	Clone before defaulting
5	MEDIUM	Verbose: true default lost when caller passes options	Fixed by cloning defaults struct
6	MEDIUM	pipeTransport.Close() race on channel close	sync.Once (consistent with rest of codebase)
7	MEDIUM	downloadPatchrightCore duplicates safeJoin traversal guard	Reuse safeJoin
8	LOW	EvalOnSelector missing isolatedContext	Added to all eval methods