refactor(rename): kb crates → kebab — Cargo packages, folders, Rust modules

프로젝트 이름 `kb` → `kebab` rename 의 첫 단계.

- workspace `Cargo.toml`: members `crates/kb-*` → `crates/kebab-*`,
  repository URL `altair823/kb` → `altair823/kebab`.
- 18 crate 폴더 rename via `git mv` (history 보존).
- 각 crate `Cargo.toml`: `name = "kb-*"` → `"kebab-*"`, path deps
  `../kb-*` → `../kebab-*`.
- 모든 `.rs`: `kb_<id>` snake-case 모듈 path 18 개 (`kb_core`,
  `kb_config`, `kb_app`, `kb_cli`, `kb_eval`, `kb_search`, `kb_chunk`,
  `kb_normalize`, `kb_source_fs`, `kb_parse_md`, `kb_parse_types`,
  `kb_store_sqlite`, `kb_store_vector`, `kb_embed`, `kb_embed_local`,
  `kb_llm`, `kb_llm_local`, `kb_rag`) → `kebab_<id>` 일괄 sed (단어
  경계 \\b 사용해 영어 문장 안의 "kb" 약어 미오염).

CLI binary 이름 (`[[bin]] name = "kb"`), 환경변수 `KB_*`, XDG paths,
tracing target, 그리고 docs sweep 은 다음 commit 에서.

## 검증

- `cargo check --workspace` clean — 모든 crate 빌드 통과 후 commit.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

crates/kebab-app/tests/common/mod.rs

@@ -0,0 +1,104 @@
+//! Shared test scaffolding for `kb-app` integration tests.
+//!
+//! Each test gets a fresh `TempDir` and a `Config` whose storage paths
+//! all point inside it, so the user's real `data_dir` / `model_dir`
+//! is never touched. The fixture workspace at
+//! `tests/fixtures/workspace/` is *copied* into the temp dir for each
+//! test so a write-side ingest can't trip on a read-only fixture
+//! tree. The default lane (no `--ignored`) opts out of embeddings via
+//! `provider = "none"` so AVX is not required.
+
+#![allow(dead_code)]
+
+use std::path::{Path, PathBuf};
+
+use kebab_config::Config;
+use tempfile::TempDir;
+
+/// Test environment: owns a `TempDir` and exposes a `Config` whose
+/// storage paths live inside it.
+pub struct TestEnv {
+    pub temp: TempDir,
+    pub workspace_root: PathBuf,
+    pub config: Config,
+}
+
+impl TestEnv {
+    /// Build an env with embeddings disabled (lexical-only). Default
+    /// lane — no AVX, no fastembed download.
+    pub fn lexical_only() -> Self {
+        let env = Self::new_inner();
+        let mut e = env;
+        e.config.models.embedding.provider = "none".to_string();
+        e.config.models.embedding.dimensions = 0;
+        e
+    }
+
+    /// Build an env with the default fastembed embedding provider.
+    /// Used by AVX-gated `#[ignore]` tests.
+    pub fn with_embeddings() -> Self {
+        Self::new_inner()
+    }
+
+    fn new_inner() -> Self {
+        let temp = tempfile::tempdir().expect("tempdir");
+        let workspace_root = temp.path().join("workspace");
+        copy_fixture_workspace(&workspace_root);
+
+        let data_dir = temp.path().join("data");
+        std::fs::create_dir_all(&data_dir).unwrap();
+        let model_dir = temp.path().join("models");
+        std::fs::create_dir_all(&model_dir).unwrap();
+
+        let mut config = Config::defaults();
+        config.workspace.root = workspace_root.to_string_lossy().into_owned();
+        // Drop the ".obsidian" / "node_modules" excludes — they bring
+        // in nothing useful for fixtures and just hide debugging.
+        config.workspace.exclude.clear();
+        config.storage.data_dir = data_dir.to_string_lossy().into_owned();
+        // Pin model_dir to the TempDir so a future fastembed-touching
+        // test can't accidentally write to the user's `~/.local/share`.
+        config.storage.model_dir = model_dir.to_string_lossy().into_owned();
+        // Drop in a small chunk policy so the fixture's small files
+        // emit at least a couple of chunks even with overlap_tokens
+        // honored.
+        config.chunking.target_tokens = 80;
+        config.chunking.overlap_tokens = 20;
+
+        Self {
+            temp,
+            workspace_root,
+            config,
+        }
+    }
+
+    pub fn scope(&self) -> kebab_core::SourceScope {
+        kebab_core::SourceScope {
+            root: self.workspace_root.clone(),
+            include: self.config.workspace.include.clone(),
+            exclude: self.config.workspace.exclude.clone(),
+        }
+    }
+}
+
+fn copy_fixture_workspace(dest: &Path) {
+    let src = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
+        .join("tests")
+        .join("fixtures")
+        .join("workspace");
+    copy_dir_recursive(&src, dest);
+}
+
+fn copy_dir_recursive(src: &Path, dest: &Path) {
+    std::fs::create_dir_all(dest).unwrap();
+    for entry in std::fs::read_dir(src).expect("read fixture dir") {
+        let entry = entry.unwrap();
+        let path = entry.path();
+        let target = dest.join(entry.file_name());
+        if path.is_dir() {
+            copy_dir_recursive(&path, &target);
+        } else {
+            std::fs::copy(&path, &target).expect("copy fixture file");
+        }
+    }
+}