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/harness/tools/computer/with-computer-env.ts

@@ -0,0 +1,66 @@
+import type { HarnessTool } from "../../types";
+
+type Params = {
+    tool: HarnessTool;
+    /**
+     * Absolute paths of the env files on the computer.
+     */
+    shell_path: string;
+    json_path: string;
+};
+
+/**
+ * Makes a computer tool run with the computer's envs. The sandbox's shells
+ * don't read a profile, so bash commands source the env file first and
+ * Python or JavaScript code loads the JSON one. The model never sees the
+ * addition; other tools pass through.
+ */
+export default function withComputerEnv({
+    tool,
+    shell_path,
+    json_path,
+}: Params): HarnessTool {
+    const shell_prefix = `[ -f ${shell_path} ] && . ${shell_path}; `;
+
+    if (tool.name == "sandbox_execute_bash") {
+        return {
+            ...tool,
+            run: ({ args, signal }) =>
+                tool.run({
+                    args: typeof args?.cmd == "string" ? { ...args, cmd: `${shell_prefix}${args.cmd}` } : args,
+                    signal,
+                }),
+        };
+    }
+
+    if (tool.name == "sandbox_execute_code") {
+        return {
+            ...tool,
+            run: ({ args, signal }) =>
+                tool.run({
+                    args:
+                        typeof args?.code == "string"
+                            ? { ...args, code: `${codePrefix({ language: args.language, json_path })}${args.code}` }
+                            : args,
+                    signal,
+                }),
+        };
+    }
+
+    return tool;
+}
+
+function codePrefix({ language, json_path }: { language?: unknown; json_path: string }) {
+    const path = JSON.stringify(json_path);
+    const lang = typeof language == "string" ? language.toLowerCase() : "python";
+
+    if (lang.startsWith("py")) {
+        return `import json as _cobble_json, os as _cobble_os; _cobble_os.environ.update(_cobble_json.load(open(${path})) if _cobble_os.path.exists(${path}) else {})\n`;
+    }
+
+    if (lang.startsWith("js") || lang.startsWith("javascript") || lang.startsWith("node")) {
+        return `try { Object.assign(process.env, JSON.parse(require("fs").readFileSync(${path}, "utf8"))); } catch {}\n`;
+    }
+
+    return "";
+}