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/audio/looks-like-missing-audio.ts

@@ -0,0 +1,14 @@
+type Params = {
+    text: string;
+};
+
+const MissingAudio =
+    /(provide|upload|share|attach|send)\b.{0,40}\baudio|can(?:'|’)?t (?:transcribe|hear|access|listen)|cannot (?:transcribe|hear|access|listen)|no audio|without (?:the |an |any )?audio|didn(?:'|’)?t (?:receive|get) (?:the |an |any )?audio/i;
+
+/**
+ * Whether a chat model's "transcript" is really it saying it got no audio.
+ * Some providers list audio input for a model but drop the audio.
+ */
+export default function looksLikeMissingAudio({ text }: Params) {
+    return text.length < 300 && MissingAudio.test(text);
+}