Add the harness, envs, per-bot models and chat attachments

- Harness: providers, model catalog synced hourly, automatic free picks,
  cooldowns, tool loop with context trimming, MCP computer tools
- Bots queue runs replies and tasks through the harness; jobs wait
  (attempt refunded) while every model is resting
- Envs: Settings > Environment, scoped general/workspace/computer,
  written to computers and redacted from tool output
- Models: Settings > Models, per-harness provider select defaulting to
  OpenRouter, and a models modal on each bot's chat (the coordinator's
  edits the defaults)
- Chat: thinking row while a reply runs, file attachments (upload,
  paste, drop) that replies read as images, audio and document text
- Fix media uploads failing after a user's first file, and private
  files being served from the public media path

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/dict/computer-dict.ts

@@ -70,3 +70,20 @@ export const ContainerPurposes = [
 ] as const;
 
 export type ContainerPurpose = (typeof ContainerPurposes)[number]["value"];
+
+/**
+ * Path of the AIO sandbox's MCP endpoint, on the computer's address.
+ */
+export const ComputerMcpPath = "/mcp";
+
+/**
+ * Sandbox MCP tools bots don't get: noise (cdp urls), skills they have no
+ * use for, and raw display control that needs pixel coordinates (the page
+ * tools cover the same ground by element).
+ */
+export const ComputerMcpExcludedTools = [
+    "browser_get_info",
+    "sandbox_load_skill",
+    "browser_gui_screenshot",
+    "browser_gui_execute_action",
+] as const;