Standards/compatibility fixes & OSC-8 links & OSC-1337 image features

• change default terminal encoding to utf8
• invert drag & drop format preferences
• handle ISO-8613-6 SGR subparameters
• default all character maps to US/ASCII when resetting
• fix reset after custom text attributes
• separate terminal full & soft reset code paths
• move vt reset calls into the terminal layer
• reset SGR attributes during soft resets
• move cursor save/restore state from per-terminal to per-screen
• rename CHA comments to match DEC docs
• support DECSET 1007 for controlling alternate scroll mode
• hoist openUrl to main namespace
• support OSC 8 for hyperlinking text
• add localization logic
• drop max-string-sequence support
• add a test to keep nassh translations in sync
• allow keybindings for unknown keys
• add a default PASS mapping for the Clear key
• use new lib.f.getOs helper
• include all profiles all the time when backing up
• implement OSC 1337 file display/transfer