#33: some sites prepend runs of ZWJ/word-joiner/invisible-times/BOM to
document.title (badging/anti-scrape); left in, they polluted 'tab list', broke
text matching, and wrecked column alignment. sanitize_title() now strips
zero-width/bidi-format chars at every title ingestion point + get_title().
#34: 'screenshot <selector>' (element capture) already worked but was
undocumented; added 'screenshot --clip x,y,w,h' for an explicit pixel region
(CDP captureScreenshot clip), documented both in --help. Verified live.