Add upload tool and related APIs (#187)

* Add utils for r2 upload

* Add the tool and new routes

* fix auth issue

* sign headers

* add comment

* use our own API key to auth signed uploads

* Restructure things slightly

* tweak

* tweak

* add comments

* tweak

* revert a thing

* twaek

* drop mime type filtering

* new incarnation of mime type filtering

* jsut allow all octet-streams

* simplify further

* tweak

* update lockfile

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Co-authored-by: Colin McDonnell <colinmcd94@gmail.com>

utils/agent.ts

@@ -2,7 +2,7 @@ import { type Agent, agents } from "../agents/index.ts";
 import type { AgentName } from "../external.ts";
 import { log } from "./cli.ts";
 import type { ResolvedPayload } from "./payload.ts";
-import type { RepoSettings } from "./repoSettings.ts";
+import type { RepoSettings } from "./runContext.ts";
 
 /**
  * Check if an agent has API keys available (from process.env)