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-tui/src/slash/commands/effort_levels.rs

@@ -0,0 +1,77 @@
+//! Shared reasoning-effort dropdown levels for `/model` and `/effort`.
+
+use kigi_shell::sampling::types::{ReasoningEffort, ReasoningEffortOption};
+
+use crate::slash::command::ArgItem;
+
+/// Effort levels in the built-in fallback menu (strongest first). `none`/`minimal`
+/// are still accepted by `ReasoningEffort::from_str` for power users.
+pub(crate) const EFFORT_LEVELS: &[ReasoningEffort] = &[
+    ReasoningEffort::Xhigh,
+    ReasoningEffort::High,
+    ReasoningEffort::Medium,
+    ReasoningEffort::Low,
+];
+
+pub(crate) fn effort_description(level: ReasoningEffort) -> &'static str {
+    match level {
+        ReasoningEffort::None => "No reasoning",
+        ReasoningEffort::Minimal => "Minimal reasoning",
+        ReasoningEffort::Low => "Faster, lighter reasoning",
+        ReasoningEffort::Medium => "Balanced reasoning",
+        ReasoningEffort::High => "Heavy reasoning",
+        ReasoningEffort::Xhigh => "Maximum reasoning",
+    }
+}
+
+/// The built-in menu used when the server sends no `reasoningEfforts`. Reproduces
+/// the historical rows: labels are the lowercase level (via `Display`),
+/// descriptions from `effort_description`. The active row is matched by value
+/// against the session effort at render time, so `default` is left unset here.
+pub(crate) fn legacy_effort_options() -> Vec<ReasoningEffortOption> {
+    EFFORT_LEVELS
+        .iter()
+        .map(|&level| ReasoningEffortOption {
+            id: level.as_str().to_string(),
+            value: level,
+            label: level.to_string(),
+            description: Some(effort_description(level).to_string()),
+            default: false,
+        })
+        .collect()
+}
+
+/// Build effort rows for autocomplete from a per-model option list.
+///
+/// - `mark_active` + `current_effort` mark the current session effort with `(active)`.
+/// - `insert_text_for` controls what is inserted on select:
+///   - `/effort`: the option id (`"deep"`)
+///   - `/model` chained phase: `"ModelName deep"`
+///
+/// `match_text` gets an `a `/`b `/…` sort prefix so the matcher's alphabetical
+/// tiebreak preserves the option order.
+pub(crate) fn build_effort_arg_items(
+    options: &[ReasoningEffortOption],
+    current_effort: Option<ReasoningEffort>,
+    mark_active: bool,
+    insert_text_for: impl Fn(&ReasoningEffortOption) -> String,
+) -> Vec<ArgItem> {
+    options
+        .iter()
+        .enumerate()
+        .map(|(idx, option)| {
+            let active = mark_active && current_effort == Some(option.value);
+            let active_suffix = if active { " (active)" } else { "" };
+            let insert_text = insert_text_for(option);
+            // Sort-key prefix: 'a' for top row, 'b' for next, etc. Only
+            // affects matcher tiebreak ordering, never rendered.
+            let sort_prefix = char::from(b'a' + idx as u8);
+            ArgItem {
+                display: format!("{}{active_suffix}", option.label),
+                match_text: format!("{sort_prefix} {insert_text}"),
+                insert_text,
+                description: option.description.clone().unwrap_or_default(),
+            }
+        })
+        .collect()
+}