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

plugins/ai/migrations/snapshot.json

@@ -8,6 +8,11 @@
           "primaryKey": true,
           "notNull": true
         },
+        "syncId": {
+          "type": "varchar",
+          "length": 255,
+          "unique": true
+        },
         "userId": {
           "type": "refUser",
           "length": 255,
@@ -191,6 +196,173 @@
         }
       ],
       "adopts": "ai_proposals"
+    },
+    "agent_sessions": {
+      "columns": {
+        "id": {
+          "type": "id",
+          "primaryKey": true,
+          "notNull": true
+        },
+        "sessionId": {
+          "type": "varchar",
+          "length": 36,
+          "notNull": true,
+          "unique": true
+        },
+        "userId": {
+          "type": "refUser",
+          "length": 255,
+          "notNull": true
+        },
+        "hostId": {
+          "type": "integer",
+          "notNull": true
+        },
+        "providerId": {
+          "type": "integer",
+          "notNull": true
+        },
+        "agent": {
+          "type": "varchar",
+          "length": 32,
+          "notNull": true
+        },
+        "model": {
+          "type": "text",
+          "notNull": true
+        },
+        "cwd": {
+          "type": "text",
+          "notNull": true
+        },
+        "executable": {
+          "type": "text",
+          "notNull": true
+        },
+        "nativeId": {
+          "type": "text"
+        },
+        "title": {
+          "type": "text"
+        },
+        "archived": {
+          "type": "boolean",
+          "notNull": true,
+          "defaultValue": false
+        },
+        "queuePaused": {
+          "type": "boolean",
+          "notNull": true,
+          "defaultValue": false
+        },
+        "draft": {
+          "type": "text"
+        },
+        "attachments": {
+          "type": "text",
+          "notNull": true,
+          "defaultValue": "[]"
+        },
+        "updatedAt": {
+          "type": "text",
+          "notNull": true
+        }
+      },
+      "indexes": [
+        {
+          "name": "idx_ai_agent_sessions_user",
+          "columns": ["userId"]
+        }
+      ]
+    },
+    "agent_events": {
+      "columns": {
+        "id": {
+          "type": "id",
+          "primaryKey": true,
+          "notNull": true
+        },
+        "sessionId": {
+          "type": "varchar",
+          "length": 36,
+          "notNull": true
+        },
+        "userId": {
+          "type": "refUser",
+          "length": 255,
+          "notNull": true
+        },
+        "seq": {
+          "type": "integer",
+          "notNull": true
+        },
+        "kind": {
+          "type": "varchar",
+          "length": 16,
+          "notNull": true
+        },
+        "text": {
+          "type": "text",
+          "notNull": true
+        },
+        "requestId": {
+          "type": "text"
+        },
+        "choices": {
+          "type": "text"
+        }
+      },
+      "indexes": [
+        {
+          "name": "idx_ai_agent_events_session_seq",
+          "columns": ["sessionId", "seq"],
+          "unique": true
+        }
+      ]
+    },
+    "agent_queue": {
+      "columns": {
+        "id": {
+          "type": "id",
+          "primaryKey": true,
+          "notNull": true
+        },
+        "sessionId": {
+          "type": "varchar",
+          "length": 36,
+          "notNull": true
+        },
+        "userId": {
+          "type": "refUser",
+          "length": 255,
+          "notNull": true
+        },
+        "promptId": {
+          "type": "varchar",
+          "length": 36,
+          "notNull": true
+        },
+        "position": {
+          "type": "integer",
+          "notNull": true
+        },
+        "text": {
+          "type": "text",
+          "notNull": true
+        },
+        "attachmentIds": {
+          "type": "text",
+          "notNull": true,
+          "defaultValue": "[]"
+        }
+      },
+      "indexes": [
+        {
+          "name": "idx_ai_agent_queue_session",
+          "columns": ["sessionId", "position"]
+        }
+      ]
     }
   }
 }