Swath coverage: Improve detection of missing sectors in dual-swath mode

[kjerram]

Recent Kilo Moana EM122 data is missing the outermost starboard sector for the second swath (when dual swath is enabled) for some files (e.g., 2021 QAT file 0012, inbound from deep to shallow). This shows up as all RX beams associated with the outermost TX sector being flagged as 'rejected' in Qimera, which is also the flag used to detect outermost soundings for the swath coverage plotter. The first outbound file (0001, shallow to deep) does not show this behavior. This came to light after feedback from a PI on board and was missed during the 2021 QAT.

Add a swath coverage plotter feature that checks for persistent mismatches between the TX sector associated with the outermost RX beam on each side, within each swath (e.g., for only swath 1 and only swath 2, if dual-swath is enabled). Warn the user if it appears that one side is consistently unable to report outermost soundings from the expected outer TX sector number for that swath number.

Alternatively, as a first pass to help users detect this, add an option to color the soundings by TX sector or swath number; this would highlight any anomalies by making the reduced coverage trends stand out with one color that is different from the remaining 'normal' outermost coverage.

See attached images for examples of inbound coverage with missing outer stbd sector on swath 2.