fix(orphans): give a rejoined PTY back to its live row instead of recovering it (#139)

fix(orphans): give a rejoined PTY back to its live row instead of recovering it

A stopped PTY can rejoin (hook restore, or `hcom start` in its own shell)
without orphan recovery, leaving a live row with no pid while the pidfile
still lists the process. Recovering it then split one agent across two names.

Ownership is now decided before recovery, by process binding, then by session
when no other PTY is bound to it. An owned PTY gets its pid, terminal context
and notify ports back. `start --orphan`, kill, stop and the TUI orphan list
all use this, and ` works. `start --as` renames the
pane.

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Co-authored-by: aannoo <aannoo@users.noreply.github.com>