26cd05e961
agentpr always read gitea/creds/unkin-agent from a bare const, so a service like repospawner could not run it as its own Gitea identity. - Replace the GiteaCredsPath const with a function: GITEA_CREDS_PATH when set, otherwise gitea/creds/<AGENT_LOGIN>. Unset env still resolves to gitea/creds/unkin-agent, so existing callers are unchanged. - Thread the creds path through fetchGiteaToken/readGiteaCreds instead of reading a package-level const, and report it in the error messages. - Make agentpr's help text login-agnostic and document both variables.