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-shell/src/extensions/prompt_meta.rs

@@ -0,0 +1,71 @@
+use serde::{Deserialize, Serialize};
+
+/// Typed metadata for a prompt `TextContent._meta` field.
+///
+/// Replaces ad-hoc `serde_json::json!()` construction on the sender side
+/// and manual `.get()` parsing on the receiver side.
+///
+/// Wire-compatible with the existing format: `{"bash_command": "ls -la"}`
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct PromptBlockMeta {
+    /// Direct bash command to execute (bypasses agent loop).
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub bash_command: Option<String>,
+}
+
+impl PromptBlockMeta {
+    /// Create meta for a direct bash command.
+    pub fn bash(command: impl Into<String>) -> Self {
+        Self {
+            bash_command: Some(command.into()),
+        }
+    }
+
+    /// Try to parse from a freeform `_meta` map.
+    pub fn from_value(value: &agent_client_protocol::Meta) -> Option<Self> {
+        serde_json::from_value(serde_json::Value::Object(value.clone())).ok()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn bash_roundtrip_serde() {
+        let meta = PromptBlockMeta::bash("ls -la");
+        let json = serde_json::to_value(&meta).unwrap();
+        let parsed: PromptBlockMeta = serde_json::from_value(json).unwrap();
+        assert_eq!(parsed.bash_command, Some("ls -la".to_string()));
+    }
+
+    #[test]
+    fn from_value_legacy_compat() {
+        let val = serde_json::json!({"bash_command": "ls"});
+        let meta = PromptBlockMeta::from_value(val.as_object().unwrap()).unwrap();
+        assert_eq!(meta.bash_command, Some("ls".to_string()));
+    }
+
+    #[test]
+    fn from_value_unrelated_meta() {
+        let val = serde_json::json!({"other": 1});
+        let meta = PromptBlockMeta::from_value(val.as_object().unwrap());
+        assert!(meta.is_some());
+        assert_eq!(meta.unwrap().bash_command, None);
+    }
+
+    #[test]
+    fn from_value_empty_object() {
+        let val = serde_json::json!({});
+        let meta = PromptBlockMeta::from_value(val.as_object().unwrap());
+        assert!(meta.is_some());
+        assert_eq!(meta.unwrap().bash_command, None);
+    }
+
+    #[test]
+    fn skip_serializing_none() {
+        let meta = PromptBlockMeta { bash_command: None };
+        let json = serde_json::to_value(&meta).unwrap();
+        assert!(!json.as_object().unwrap().contains_key("bash_command"));
+    }
+}