Table output doesn't neutralize terminal control characters in server data #206

nsc/output/table.py (_format_cell, _format_colored) runs cell values through Rich's markup escape(). That stops [..] markup, but control characters such as ESC (\x1b) and BEL, and bidi overrides, still reach the terminal. A NetBox object whose name or description contains a terminal escape sequence can therefore drive the user's terminal when listed in table output: retitle it, clear the screen, or spoof text.

#205 fixed the same class of problem for the TTY error panel with _printable in nsc/output/errors.py, which shows control and format characters as visible \x.. escapes. The table formatter, and any other Rich-rendered path that prints server text (e.g. the --explain panel in nsc/output/explain.py and the TUI), should get the same treatment. Moving _printable to a shared helper would cover all of them.

JSON, JSONL, YAML and CSV output already escape or quote these characters, or don't target a terminal, so they're out of scope.

Found during the security review of #205.