Workers at one of the West Coast’s most prominent museums are unionizing.  On Wednesday, more than 100 Seattle Art Museum employees working across more than 20 front- and back-end departments announced their intent to unionize, the latest effort in a growing movement of labor organizing at museums and fine art institutions around the country in the last six years.  Organizers announced their intent to unionize as the Seattle Art Museum Workers United in a letter delivered to the museum Director and CEO Scott Stulen Wednesday morning.  “Our solidarity is a movement to improve working conditions in alignment with SAM’s mission, vision, and core values,” organizers wrote.  “The challenges we face, such as unsustainable wages, subpar health benefits, and siloed, top-down decision-making, are undeniable, systemic, and have persisted across administrations.” Seattle Art Museum leadership did not immediately respond to requests for comment Wednesday morning.…