M0: compilable skeleton — Kigi 0.1.0 fork surgery

Hard fork of xai-org/grok-build (Apache-2.0) re-targeted as Kigi, an
unofficial Kimi Code CLI community build.

Rename & identity
- 72 xai-*/xai-grok-* crates -> kigi-* (explicit: xai-grok-pager-bin ->
  kigi-bin [binary `kigi`], xai-grok-pager -> kigi-tui; rest mechanical);
  ptyctl, ptyctl-cli, third_party/ unchanged; proto package
  xai.grok.tools.v1 -> kigi.tools.v1
- Config home ~/.kigi (KIGI_SHARE_DIR override), env prefix GROK_* ->
  KIGI_*, `kigi --version` carries the unofficial-community-build notice
- clap identity, help text, startup banner, prompt templates rebranded
  (templates re-encrypted)

Deletions (PRD removal list #5/#6/#7/#9/#10)
- voice input (xai-grok-voice) and all TUI wiring
- telemetry: Mixpanel client, external OTel stream, Sentry, OTLP layers,
  trace/GCS/S3 upload queues (kigi-file-utils halved), workspace upload
  module & dc_log, heap-profile uploader, auth-diagnostics uploader,
  session-analytics halves of feedback; local zero-egress observability
  preserved in new kigi-log crate (unified log, --debug firehose,
  subsystem file logs, opt-in instrumentation)
- announcements (crate, remote-settings fields, TUI surfaces)
- plugin marketplace (crate, sources/browse/CTA/extensions-modal tab);
  direct plugin install/uninstall/update via kigi-agent git_install kept
- relay/gateway/assets endpoints and features (agent relay, headless
  relay transport, gateway bridge, LeaderEnvUrls); leader IPC socket now
  ~/.kigi/leader.sock + KIGI_LEADER_SOCKET, no ws-url derivation
- functional types rehomed instead of deleted: PermissionMode ->
  kigi-config-types, McpInitStrategy -> kigi-mcp, PrCreationSource ->
  session signals, TerminalDiagnostics -> kigi-pager-render, agent_id ->
  shell util

Endpoints
- kigi-env rewritten: single production KigiEndpoints {coding_api_base_url
  https://api.kimi.com/coding/v1 (KIGI_CODE_BASE_URL), oauth_host
  https://auth.kimi.com (KIGI_OAUTH_HOST), update_base_url (GitHub
  Releases API), upgrade_page_url}; GrokBuildEnvironment enum deleted

Toolchain & workspace hygiene
- Rust 1.97.0 pinned; edition 2024; full cargo update; git2 hoisted to
  workspace at 0.21 (Option->Result API migration), quick-xml 0.41
- Root Cargo.toml hand-maintained (PRD §8.1): version 0.1.0 inherited by
  all members, members sorted, unused deps pruned
- cargo-deny advisories gate (deny.toml with documented transitive
  exceptions); CI workflow (check/clippy/fmt/deny/test, macOS+Linux)
- cross-crate test seams re-gated behind `test-support` cargo feature;
  insta snapshot baselines renamed to the kigi_tui prefix
- clippy --workspace --all-targets: zero warnings; fmt clean

Fixes surfaced by the port
- updater probe/installer divergence (bin/kigi vs bin/grok symlink set)
- idle model-metadata refresh dead under KIGI_CODE_BASE_URL override
  (new is_effective_coding_endpoint_url, loopback+override aware)
- macOS symlinked-TMPDIR fixture canonicalization (foreign_sessions,
  fast-worktree); RSS measurement tests serialized via serial_test

Docs & legal (Apache §4)
- NOTICE added (upstream attribution + change statement); THIRD-PARTY
  notices sustained; kigi-tools ported-code notices extended; README,
  CONTRIBUTING, SECURITY, AGENTS.md rewritten

Out of scope for M0 (tracked): Kimi auth/inference (M1), search/fetch,
command parity, config import (M2), Computer Hub excision & final
brand-token sweep (M2), distribution & self-update rewrite (M3).

crates/codegen/kigi-tools/src/implementations/grok_build/grep/ripgrep.rs

@@ -0,0 +1,81 @@
+use std::path::PathBuf;
+use std::sync::OnceLock;
+
+#[cfg(bundle_rg)]
+const RG_BYTES: &[u8] = include_bytes!(concat!(
+    env!("OUT_DIR"),
+    "/bundle-rg/rg-",
+    env!("KIGI_TOOLS_RG_VER"),
+    "-",
+    env!("KIGI_TOOLS_RG_TARGET"),
+    ".bin"
+));
+
+#[cfg(bundle_rg)]
+fn resolve_bundled_rg() -> std::io::Result<PathBuf> {
+    use std::fs;
+    #[cfg(unix)]
+    use std::os::unix::fs::PermissionsExt;
+    let p = crate::util::kigi_home().join("vendor").join(concat!(
+        "rg-",
+        env!("KIGI_TOOLS_RG_VER"),
+        "-",
+        env!("KIGI_TOOLS_RG_TARGET")
+    ));
+    if !p.exists() {
+        fs::create_dir_all(p.parent().unwrap())?;
+        fs::write(&p, RG_BYTES)?;
+        #[cfg(unix)]
+        {
+            let mut perms = fs::metadata(&p)?.permissions();
+            perms.set_mode(0o755);
+            fs::set_permissions(&p, perms)?;
+        }
+    }
+    Ok(p)
+}
+
+/// Get the path to the ripgrep executable.
+///
+/// In release builds with bundling enabled, this extracts the bundled ripgrep
+/// binary to ~/.kigi/vendor/ and returns that path.
+/// Otherwise, assumes `rg` is in PATH.
+pub fn rg_path() -> PathBuf {
+    static RG_EXEC: OnceLock<PathBuf> = OnceLock::new();
+    RG_EXEC
+        .get_or_init(|| {
+            #[cfg(bundle_rg)]
+            {
+                resolve_bundled_rg().unwrap_or_else(|_| PathBuf::from("rg"))
+            }
+            #[cfg(not(bundle_rg))]
+            {
+                // RG_BIN_PATH: explicit override (tests / packaging can set this).
+                if let Ok(p) = std::env::var("RG_BIN_PATH") {
+                    return PathBuf::from(p);
+                }
+                // Some hermetic test runners set RUNFILES_DIR and ship rg as a
+                // data dependency rather than on PATH. Scan for a directory
+                // entry containing "ripgrep_hermetic" and prefer arch-scoped
+                // paths when present.
+                if let Ok(rf) = std::env::var("RUNFILES_DIR") {
+                    let base = PathBuf::from(rf);
+                    if let Ok(entries) = std::fs::read_dir(&base) {
+                        for entry in entries.flatten() {
+                            let name = entry.file_name();
+                            if name.to_string_lossy().contains("ripgrep_hermetic") {
+                                for sub in ["amd64/rg", "arm64/rg", "rg"] {
+                                    let candidate = entry.path().join(sub);
+                                    if candidate.exists() {
+                                        return candidate;
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+                PathBuf::from("rg")
+            }
+        })
+        .clone()
+}