feat(ai): add remote coding agent sessions for SSH hosts (#1545)

* feat(ai): add host coding agent sessions with configured providers

* Wait for agent initialization and shutdown before resuming sessions

* Keep Pi transcripts outside its configuration migration directory

* Cover Pi session directory separation

* Update core permission catalog expectations for remote agents

* Install remote agent runtimes from verified official sources

* Wait for the identity panel credentials request in its test

* Add scoped SSH forwarding setup for remote agents

* Verify forwarding setup through a fresh SSH connection

* Bound the SSH forwarding verification timeout

* Return the forwarding verification callback result

* fix(ai): support agent send and interrupt keyboard shortcuts

* feat(ai): add agent queues attachments worktrees and session recovery

* fix(ai): handle deleted workspace paths and duplicate status events

* fix(ai): accept file references in root workspaces

* fix(ai): refresh paused queues after agent errors

* fix(ai): store agent sessions in plugin tables and lock down OpenCode

Agent sessions lived in a single ctx.kv value holding up to 2000 events,
which passed the 256 KB kv limit within minutes of a normal run. Every
save after that failed, so history, nativeId, queue and archive changes
were lost and every event wrote a kv audit row.

Sessions, events and queued prompts now have their own tables. A running
agent appends events in batches at most once a second with a lazy save;
session and queue changes save immediately. Prompts, drafts and stored
event text are capped in UTF-8 bytes to fit MySQL TEXT. kv:own is no
longer requested.

The OpenCode server now requires a per-session password, so other local
accounts on the host cannot drive the agent through its loopback port.

* test(upgrade): include agent session tables in the reviewed upgrade SQL

src/backend/tests/plugins/permissions-rbac.test.ts

@@ -378,6 +378,7 @@ describe("shipped manifests keep their permission ids", () => {
       "ai.apply_proposals",
       "ai.services.use",
       "ai.secrets.share",
+      "ai.agents",
     ]);
   });