Add commands to switch between ECA chat buffers

[thanosapollo]

• Add eca-switch-to-chat to switch to any active ECA chat buffer.
• Add eca-switch-to-project-chat to switch within the current project/session.
• Reuse ECA’s chat display behavior so visible chat windows are selected and hidden chats respect existing side-window settings.

[ericdallo]

@thanosapollo doesn't that work already with just eca command?

[thanosapollo]

Hello @ericdallo

AFAICT, eca either switches to the “current session” chat (or starts
a new one), but it doesn’t let the user pick among already-open chat
buffers/sessions.

It would be useful to have a dedicated command for that:

• eca-switch-to-chat: list all current sessions and let the user
  select one (across projects).

And a project-scoped variant:

• eca-switch-to-project-chat: similar to eca, limited to the
  current project but lets user select a session; this makes it a good fit for project-prefix-map
  (C-x p) and would list all sessions for the project.

edit: Thank you for working on this, recently switched and I'm really enjoying it.

[ericdallo]

@thanosapollo did you try eca-workspaces to select and open a chat?
I'm ok with a new one to chats of the session tho

[thanosapollo]

@ericdallo yes, eca-workspaces provides a tree view for browsing
sessions/chats. This adds a faster minibuffer workflow for jumping
directly to a chat.

eca-switch-to-project-chat is scoped to the current ECA session and
prompts only when there are multiple chats. eca-switch-to-chat is
the broader cross-session variant.

The shape is similar to project-switch-to-buffer /
erc-switch-to-buffer, and also close to
claude-code-ide-list-sessions for the cross-session case.

[ericdallo]

Got it, I think that's fine, just wanna avoid too many commands and options to existing stuff, but sounds fair enough, please mention the new commands in readme as well

[thanosapollo]

done, thanks @ericdallo

[ericdallo]

Thank you