docs: point terminal users at codeman tui instead of the sc chooser

codeman tui supersedes the sc bash chooser: it reaches sessions 10+,
carries the server's real states instead of a static list, and leaves an
attach with one key. Every place that told a user to run sc now names the
tui equivalent, including the two wiki pages and install.sh's next-steps
banner. Both wiki pages also carried the wrong detach chord (Ctrl+A D;
the socket's prefix is C-b), which the tui makes moot.

Source comments that explained themselves as "the sc -l replacement" now
just say what they do. docs/tui-plan.md and CHANGELOG.md are historical
records and keep their references.

docs/wiki/Core-Concepts.md

@@ -88,7 +88,7 @@ would. That indirection buys:
 - **Real scrollback.** History is held by tmux, so reconnecting replays what happened while
   you were gone instead of starting from blank.
 - **Attach from anywhere else.** The same session is reachable from a terminal over SSH
-  with the `sc` chooser, or plain `tmux -L codeman attach`.
+  with `codeman tui`, or plain `tmux -L codeman attach`.
 - **Secrets off the command line.** Environment overrides are injected with socket-scoped
   `tmux setenv` rather than being visible in the spawn command.