agents: drop root, run as per-agent unix user with passwordless sudo (#658)

hive-c0re/src/lifecycle.rs

@@ -22,9 +22,20 @@ pub const MANAGER_PORT: u16 = 8000;
 /// Mount point of the per-agent runtime directory inside the container.
 pub const CONTAINER_RUNTIME_MOUNT: &str = "/run/hive";
 
-/// Mount point of the per-agent Claude credentials dir inside the container.
-/// Persistent across destroy/recreate so OAuth login survives.
-pub const CONTAINER_CLAUDE_MOUNT: &str = "/root/.claude";
+/// Where the per-agent Claude credentials dir mounts inside the
+/// container. Pre-#658 this was a constant (`/root/.claude`, because
+/// every agent ran as root). With the user-named-after-agent shape
+/// the harness service runs as a non-root unix user whose home is
+/// `/home/<agent>/`, so the mount path now varies per agent —
+/// `container_claude_mount(name)` returns `/home/<name>/.claude`
+/// for sub-agents and `/home/hm1nd/.claude` for the manager.
+/// `claude` inside the container reads `$HOME/.claude` and the
+/// service environment sets `HOME` to the same path, so the OAuth
+/// session survives container restarts the same way the constant
+/// did.
+pub fn container_claude_mount(name: &str) -> String {
+    format!("/home/{name}/.claude")
+}
 
 /// Mount point of the shared directory accessible to all agents.
 /// All agents can read/write here; agents should only put things they're
@@ -150,7 +161,14 @@ pub async fn spawn(
     // before `nixos-container create` so the `--flake meta#<name>`
     // ref resolves.
     let agents = agents_after_spawn(name).await?;
-    crate::meta::sync_agents(hyperhive_flake, dashboard_port, operator_pronouns, context_window_tokens, &agents).await?;
+    crate::meta::sync_agents(
+        hyperhive_flake,
+        dashboard_port,
+        operator_pronouns,
+        context_window_tokens,
+        &agents,
+    )
+    .await?;
     let container = container_name(name);
     let flake_ref = format!("{}#{name}", crate::meta::meta_dir().display());
     run(&["create", &container, "--flake", &flake_ref]).await?;
@@ -298,7 +316,14 @@ pub async fn rebuild(
     // got added directly via `nixos-container create` outside
     // hive-c0re).
     let agents = agents_for_meta(None).await?;
-    crate::meta::sync_agents(hyperhive_flake, dashboard_port, operator_pronouns, context_window_tokens, &agents).await?;
+    crate::meta::sync_agents(
+        hyperhive_flake,
+        dashboard_port,
+        operator_pronouns,
+        context_window_tokens,
+        &agents,
+    )
+    .await?;
     // Then bump just this agent's input — picks up whatever
     // `applied/<n>/main` currently points at (deployed/<latest>).
     // Commits the lock if it changed.
@@ -860,10 +885,14 @@ fn set_nspawn_flags(
     // below are gated on `container == MANAGER_NAME` anyway.
     let agent_name = container.strip_prefix(AGENT_PREFIX).unwrap_or(container);
 
-    // Claude credentials always land at /root/.claude so the
-    // `claude` CLI (which reads $HOME/.claude) finds them without
-    // any HOME override.
-    let claude_mount = CONTAINER_CLAUDE_MOUNT;
+    // Claude credentials land at `/home/<agent>/.claude` so the
+    // `claude` CLI (which reads `$HOME/.claude`) finds them. The
+    // harness service's environment sets `HOME` to the same path
+    // (`agent-base.nix` / `manager.nix`), so no `--setenv` plumbing
+    // is needed here — the bind alone is enough. Pre-#658 the mount
+    // was the constant `/root/.claude` because the service ran as
+    // root.
+    let claude_mount = container_claude_mount(agent_name);
 
     let mut binds = format!(
         "--bind={runtime}:{CONTAINER_RUNTIME_MOUNT} --bind={claude}:{claude_mount} --bind={shared}:{CONTAINER_SHARED_MOUNT}",
@@ -934,8 +963,7 @@ fn set_nspawn_flags(
         // `setup_proposed` seeds this dir before spawn reaches here,
         // but create defensively so a missing repo degrades to an
         // empty RO dir instead of a container that won't boot.
-        std::fs::create_dir_all(&config_dir)
-            .with_context(|| format!("create {config_dir}"))?;
+        std::fs::create_dir_all(&config_dir).with_context(|| format!("create {config_dir}"))?;
         let _ = write!(binds, " --bind-ro={config_dir}:/agents/{agent_name}/config");
     }
     let bind_flag = format!("EXTRA_NSPAWN_FLAGS=\"{binds}\"");
@@ -1138,6 +1166,9 @@ mod tests {
             .await
             .expect("git rev-list");
         let count = String::from_utf8_lossy(&out.stdout).trim().to_owned();
-        assert_eq!(count, "1", "expected exactly one commit after idempotent call");
+        assert_eq!(
+            count, "1",
+            "expected exactly one commit after idempotent call"
+        );
     }
 }

hive-c0re/src/meta.rs

@@ -401,6 +401,14 @@ where
           modules = [
             input.nixosModules.default
             {
+              # Drop root (#658): the harness service inside the
+              # container runs as a non-root unix user named after
+              # the agent (`damocles`, `iris`, `hm1nd`, …). UID
+              # auto-assigned by NixOS per mara on #658; the per-
+              # agent override here is what makes `hyperhive.user.name`
+              # match the agent's identity instead of the harness-
+              # base default of `"agent"`.
+              hyperhive.user.name = name;
               programs.git.config.user = {
                 name = name;
                 email = "${name}@hyperhive";