refactor: use static gateway skill instead of fetching on spawn

Remove the dynamic `onecli.getGatewaySkill()` fetch from `buildMounts` —
the skill content ships as a static SKILL.md. This avoids adding latency
to every container spawn and dirtying the source tree at runtime.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/container-runner.ts

@@ -132,7 +132,7 @@ async function spawnContainer(session: Session): Promise<void> {
   // buildMounts and buildContainerArgs so side effects (mkdir, etc.) fire once.
   const { provider, contribution } = resolveProviderContribution(session, agentGroup, containerConfig);
 
-  const mounts = await buildMounts(agentGroup, session, containerConfig, contribution);
+  const mounts = buildMounts(agentGroup, session, containerConfig, contribution);
   const containerName = `nanoclaw-v2-${agentGroup.folder}-${Date.now()}`;
   // OneCLI agent identifier is always the agent group id — stable across
   // sessions and reversible via getAgentGroup() for approval routing.
@@ -239,12 +239,12 @@ function resolveProviderContribution(
   return { provider, contribution };
 }
 
-async function buildMounts(
+function buildMounts(
   agentGroup: AgentGroup,
   session: Session,
   containerConfig: import('./container-config.js').ContainerConfig,
   providerContribution: ProviderContainerContribution,
-): Promise<VolumeMount[]> {
+): VolumeMount[] {
   const projectRoot = process.cwd();
 
   // Per-group filesystem state lives forever after first creation. Init is
@@ -252,23 +252,6 @@ async function buildMounts(
   // is a no-op for groups that have spawned before.
   initGroupFilesystem(agentGroup);
 
-  // Fetch the latest gateway skill from the API; fall back to the static copy.
-  const skillDir = path.join(projectRoot, 'container', 'skills', 'onecli-gateway');
-  const skillPath = path.join(skillDir, 'SKILL.md');
-  const fallbackPath = path.join(skillDir, 'SKILL.fallback.md');
-  try {
-    const skill = await onecli.getGatewaySkill();
-    const existing = fs.existsSync(skillPath) ? fs.readFileSync(skillPath, 'utf8') : '';
-    if (skill && skill !== existing) {
-      fs.writeFileSync(skillPath, skill);
-    }
-  } catch {
-    if (!fs.existsSync(skillPath) && fs.existsSync(fallbackPath)) {
-      fs.copyFileSync(fallbackPath, skillPath);
-    }
-    log.warn('Could not fetch gateway skill from OneCLI API; using static fallback');
-  }
-
   // Sync skill symlinks based on container.json selection before mounting.
   const claudeDir = path.join(DATA_DIR, 'v2-sessions', agentGroup.id, '.claude-shared');
   syncSkillSymlinks(claudeDir, containerConfig);