M2 audit: excise the Computer Hub stack — Kigi's last remote-cloud surface

Removed root-and-branch for the zero-egress guarantee (the hub was xAI's
remote-workspace/cloud-sandbox service):

- Crates deleted: kigi-computer-hub-core, kigi-computer-hub-sdk,
  kigi-computer-hub-mcp-adapter, kigi-workspace-client (hub-proxied
  workspace RPC client), and kigi-tracing (its sole network path was the
  OTLP gRPC exporter; zero consumers remained). kigi-tracing-macros
  (purely local) stays.
- kigi-workspace: every hub surface deleted — hub server/channel/auth,
  HITL-over-hub permissions, donation/metrics pumps, file upload RPCs,
  hub tool-snapshot merge (resolve pipeline is MCP-only now),
  WorkspaceOps::Proxy. Local worktrees, sessions, leader IPC, MCP, and
  the ACP permission prompt path are untouched; LocalRegistry re-homed
  into kigi-tool-runtime on the existing ToolDyn types so in-process
  tool dispatch is unchanged.
- kigi-shell: leader workspace-exposure control surface (incl. the
  wss://computer-hub... URL), [hub] config, ObservabilityBridge, hub
  WebSocket proxy, dead OTLP config knobs. ClientMode::Headless (never
  constructed) removed.
- kigi-tui/bin: hidden `kigi workspace` command removed (`kigi
  worktree` stays).
- Renames: --xai-api-base-url → --api-base-url / KIGI_API_BASE_URL /
  [endpoints] api_base_url (serde alias keeps old configs working; the
  flag feeds BYOK/custom-endpoint routing, not main inference);
  grok_version → kigi_version in inspect/models-cache/trace metadata
  (old caches self-heal via version-mismatch refetch).
- Dependency tree: dropped fastrace*, opentelemetry-otlp/http/proto,
  tokio-tungstenite from the workspace; fixed the 4 real useless_format
  violations the fastrace lint allowance was masking and removed the
  allowance.
- marketplaceAllowlist kept: it gates the LOCAL plugin-marketplace
  feature, not an xAI service.

Known §9 leftover (deliberate, for the M3 sweep): the BYOK default base
URL string. Gates: workspace check/clippy 0/0, fmt, deny ok; suites
green (workspace 1042, shell 4918, tui 6634, tools 2608, tool-runtime
47, mcp 154).

crates/codegen/kigi-shell/tests/git_contention_e2e.rs

@@ -432,7 +432,7 @@ fn git_rebase_refresh_storm_e2e() {
     unsafe {
         std::env::set_var("KIGI_SHARE_DIR", kigi_home.path());
         std::env::set_var("KIGI_CODE_BASE_URL", server.url());
-        std::env::set_var("KIGI_XAI_API_BASE_URL", server.url());
+        std::env::set_var("KIGI_API_BASE_URL", server.url());
         std::env::set_var("XAI_API_KEY", "test-key-for-ci");
         std::env::set_var("KIGI_TELEMETRY_ENABLED", "false");
         std::env::set_var("KIGI_FEEDBACK_ENABLED", "false");

crates/codegen/kigi-shell/tests/session_load_perf.rs

@@ -626,7 +626,7 @@ async fn full_session_load_e2e() {
         std::env::set_var("KIGI_INSTRUMENTATION", "log");
         std::env::set_var("KIGI_INSTRUMENTATION_LOG", &instr_log);
         std::env::set_var("KIGI_CODE_BASE_URL", server.url());
-        std::env::set_var("KIGI_XAI_API_BASE_URL", server.url());
+        std::env::set_var("KIGI_API_BASE_URL", server.url());
         std::env::set_var("XAI_API_KEY", "test-key-for-ci");
         std::env::set_var("KIGI_TELEMETRY_ENABLED", "false");
         std::env::set_var("KIGI_FEEDBACK_ENABLED", "false");

crates/codegen/kigi-shell/tests/test_built_binary_e2e.rs

@@ -1330,7 +1330,7 @@ async fn test_headless_managed_config_byok_sends_authorized_requests() {
             r#"
 [endpoints]
 deployment_key = "test-deployment-key"
-xai_api_base_url = "{url}"
+api_base_url = "{url}"
 
 [model.kigi-build]
 api_backend = "responses"

crates/codegen/kigi-shell/tests/test_leader_soak.rs

@@ -137,7 +137,7 @@ async fn leader_soak_churning_clients_no_leaks_no_zombies() {
     unsafe {
         std::env::set_var("KIGI_SHARE_DIR", kigi_home.path());
         std::env::set_var("KIGI_CODE_BASE_URL", server.url());
-        std::env::set_var("KIGI_XAI_API_BASE_URL", server.url());
+        std::env::set_var("KIGI_API_BASE_URL", server.url());
         std::env::set_var("XAI_API_KEY", "test-key-for-ci");
         std::env::set_var("KIGI_TELEMETRY_ENABLED", "false");
         std::env::set_var("KIGI_FEEDBACK_ENABLED", "false");

crates/codegen/kigi-shell/tests/test_mcp_permission_persistence.rs

@@ -16,7 +16,7 @@ use kigi_workspace::permission::types::{
 };
 use kigi_workspace::permission::{
     AccessKind, ClientType, Decision, PermissionCommand, PermissionHandle, PermissionState,
-    spawn_permission_manager, spawn_permission_manager_with_hub,
+    spawn_permission_manager,
 };
 use serial_test::serial;
 use tokio::sync::{mpsc, oneshot};
@@ -221,6 +221,7 @@ async fn run_actor_test_full<F, Fut>(
                 vec![],
                 initial_yolo,
                 None,
+                true,
             );
             body(handle, gw, cwd).await;
         })
@@ -357,7 +358,7 @@ async fn policy_ask_suppresses_mcp_tool_allowlist() {
 
             let (gw, _gw_task) = fake_gateway();
             // Gate OFF so the `ask` rule stays a hard floor over the grant.
-            let (handle, _events) = spawn_permission_manager_with_hub(
+            let (handle, _events) = spawn_permission_manager(
                 make_session_id(),
                 gw.sender.clone(),
                 cwd.clone(),
@@ -368,7 +369,6 @@ async fn policy_ask_suppresses_mcp_tool_allowlist() {
                 false,
                 None,
                 false, // remember_tool_approvals
-                None,
             );
 
             // Script an outright reject so we can confirm the prompt fires.
@@ -408,7 +408,7 @@ async fn policy_ask_suppresses_mcp_server_allowlist() {
 
             let (gw, _gw_task) = fake_gateway();
             // Gate OFF so the `ask` rule stays a hard floor over the grant.
-            let (handle, _events) = spawn_permission_manager_with_hub(
+            let (handle, _events) = spawn_permission_manager(
                 make_session_id(),
                 gw.sender.clone(),
                 cwd.clone(),
@@ -419,7 +419,6 @@ async fn policy_ask_suppresses_mcp_server_allowlist() {
                 false,
                 None,
                 false, // remember_tool_approvals
-                None,
             );
 
             gw.expected.send(("reject-once".to_string(), None)).unwrap();
@@ -463,6 +462,7 @@ async fn policy_deny_takes_precedence_over_mcp_allowlist() {
                 vec![],
                 false,
                 None,
+                true,
             );
 
             // Do NOT script a response: a policy Deny must short-circuit