feat(server,web,mobile): an agent sets up a link to another environment#17129

fix(web,mobile): a minted pairing code carries the access the link asks for

feat(web,mobile): pick a T3 Connect machine when linking

fix(server): a thread waits on its link card after the agent's turn ends

fix(web,mobile): each link answer mints its own pairing code

fix(web): the link dialog starts fresh each time it opens

fix(server): a slow machine no longer holds up every link card's answer

fix(server): a link card stays answerable after a steer, and Stop shows no new one

fix(server): an expired link goes through the link card

fix(server): a link card's id names the provider session that asked

feat(server,web,mobile): an agent sets up a link to another environment