[Feature]: Command for deleting sessions

[neal-kyle]

Problem

There doesn't seem to be a way to delete sessions.

Proposal

If a command like /session-delete or something like that could be introduced, that would help prevent sessions from piling up.

Done criteria (optional)

When sessions are clearable?

[georgernstgraf]

Yes, so when we list the sessions with /sessions in the Telegram interface, nice buttons appear. And now we're looking for a way to have a trash can icon on these buttons, where you can then also delete the respective session. Or a different option, a more suitable option in the user interface, to not only select the appearing session but also to be able to delete it.

We should also consider that deleting a session should not be possible erroneously, just as the OpenCode User Interface requires a double confirmation when one wants to delete a session.

[georgernstgraf]

Implementation Plan

Approach: Separate /session_delete command following the established /tasklist pattern

No OpenCode server-side auto-pruning exists — the SDK Session type has only time.created/time.updated/time.archived fields, no TTL/expiry/retention. Sessions accumulate until explicitly deleted.

Flow (two-stage interactive)

1. /session_delete → paginated list of sessions as inline keyboard buttons
2. Click a session → detail view with [Delete] [Cancel]
3. Delete → calls opencodeClient.session.delete({ sessionID }), clears interaction, shows success. If it was the current session, resets it.

Files

File	Change
src/bot/commands/session-delete.ts	Create — ~200 lines
src/bot/commands/definitions.ts	Add { command: "session_delete", descriptionKey: "cmd.description.session_delete" }
src/bot/index.ts	Import + register command + callback handler
src/i18n/en.ts	Add ~14 keys
src/i18n/de.ts	Add ~14 German translations
src/i18n/ru.ts	Add ~14 Russian translations
src/i18n/es.ts	Add ~14 Spanish translations
src/i18n/fr.ts	Add ~14 French translations
src/i18n/zh.ts	Add ~14 Chinese translations

Key design decisions

• Uses interactionManager with kind: "custom", flow: "session_delete" (same as /tasklist)
• Two-stage metadata: list → detail (detail view serves as implicit confirmation)
• Reuses pagination logic from existing /sessions command (loadSessionPage)
• Callback prefix sesdel: avoids collision with existing session: prefix
• isForegroundBusy() guard like all other commands
• One delete per invocation (exits after delete, like /tasklist)