§9 acceptance: grep-zero sweep — every internal x.ai/grok identifier renamed

The PRD's first acceptance gate now holds: grep -RinE '\bx\.ai\b|grok'
crates/ --include='*.rs' → 0 matches (exempt: NOTICE and third-party
license archives, README provenance, and the required 'Based on Grok
Build Open Source' attribution, now sourced from version_attribution.txt).

Wire-visible renames (both sides in this repo, changed in lockstep):
- Auth method id 'grok.com' → 'kimi-code' (AuthMethodKind::KimiCode).
- Every x.ai/* and _x.ai/* ACP ext method and meta key → kigi/* /
  _kigi/* (~200 names; grokShell → kigiShell). Session-file replay keeps
  a read-side alias for the legacy '_x.ai/session/update' method so
  existing updates.jsonl histories load; writes emit only the new name
  (both directions test-pinned).
- Agent types grok-build* → kigi* with a documented legacy-prefix alias
  at resolution time so persisted sessions keep resolving.
- ToolNamespace/BuiltinAgentName GrokBuild* → Kigi* (wire snake_case
  kigi/kigi_concise/kigi_hashline; schema regenerated); grok_build
  implementation dirs renamed to kigi*.
- x-grok-* headers → x-kigi-*, __GROK_* sentinels → __KIGI_*, themes
  grokday/groknight → kigiday/kiginight (old persisted values fall back
  to the default theme), web_fetch allowlist xAI hosts → kimi.com +
  moonshot platforms, changelog CDN → this repo, grok-build changelog
  archives deleted.
- BYOK default endpoint removed: [endpoints] api_base_url is now truly
  optional with NO default — consumers fail fast with the flag name when
  unset (no silent x.ai egress). Mock harnesses inject it explicitly.
- System-prompt identity fixed: 'released by xAI' → 'an unofficial
  community CLI for Kimi' (template + regenerated encrypted form).

Also repaired pre-existing grok-era test debt found by the sweep: the
stale trace_classify default-model pin, the grok-pager UA label test,
pty-harness stale-binary reuse and non-hermetic moonshot routing (a PTY
test could previously reach the real api.moonshot.cn), and the outdated
oauth fixture scope key.

Gates: §9 grep 0; fmt clean; workspace check/clippy 0/0 (-D warnings);
FULL cargo test --workspace: 234 suites, 21,961 passed, 0 failed;
deny advisories ok.

crates/codegen/kigi-pager-pty-harness/src/flows.rs

@@ -67,12 +67,13 @@ pub fn inference_request_count(content: &ContentController) -> usize {
         .count()
 }
 
-/// Seed a fake xAI OAuth entry into the isolated home's `auth.json` so the
-/// shell has session auth (the harness's `XAI_API_KEY` is ApiKey/BYOK mode
-/// and never enters the auth manager). Load-bearing details: the scope key
-/// must be `<issuer>::<client_id>`, `auth_mode` must be `oidc`, and
-/// `expires_at` must be far-future so no network refresh is attempted; the
-/// mock server accepts any bearer. Pair with [`oauth_env_for_pager`].
+/// Seed a fake Kimi Code OAuth entry into the isolated home's `auth.json` so
+/// the shell has session auth (the harness's `XAI_API_KEY` is ApiKey/BYOK mode
+/// and never enters the auth manager). Load-bearing details: the map key must
+/// be the Kimi Code scope key (`oauth/kimi-code`), `auth_mode` must be
+/// `oauth`, and `expires_at` must be far-future so no network refresh is
+/// attempted; the mock server accepts any bearer. Pair with
+/// [`oauth_env_for_pager`].
 pub fn seed_fake_oauth(content: &ContentController, user: &str) {
     let kigi_home = content.home().join(".kigi");
     std::fs::create_dir_all(&kigi_home).expect("create temp .kigi");
@@ -80,16 +81,14 @@ pub fn seed_fake_oauth(content: &ContentController, user: &str) {
         kigi_home.join("auth.json"),
         format!(
             r#"{{
-  "https://auth.x.ai::b1a00492-073a-47ea-816f-4c329264a828": {{
+  "oauth/kimi-code": {{
     "key": "pty-test-oauth-token",
     "auth_mode": "oauth",
     "create_time": "2026-01-01T00:00:00Z",
     "user_id": "{user}",
     "email": "{user}@test.invalid",
     "expires_at": "2030-01-01T00:00:00Z",
-    "refresh_token": "pty-test-refresh-token",
-    "oidc_issuer": "https://auth.x.ai",
-    "oidc_client_id": "b1a00492-073a-47ea-816f-4c329264a828"
+    "refresh_token": "pty-test-refresh-token"
   }}
 }}"#
         ),