refactor(rename): kb → kebab — binary, env vars, XDG paths, file renames

두 번째 commit. 사용자 facing surface (CLI binary, env vars, XDG paths)
+ 코드 안 single-letter token (`KB_`, `kb.sqlite`, `/kb/`, tracing
target) 일괄 rename. 그리고 3 개 file rename:

- 디자인 doc `2026-04-27-kb-final-form-design.md` →
  `2026-04-27-kebab-final-form-design.md`
- 최초 보고서 `kb_local_rust_report.md` → `kebab_local_rust_report.md`
- workspace ignore `.kbignore` → `.kebabignore`

## 변경

- `crates/kebab-cli/Cargo.toml`: `[[bin]] name = "kb"` → `"kebab"`.
- `crates/kebab-cli/src/main.rs`: `#[command(name = "kb", …)]` →
  `name = "kebab"`.
- 모든 `KB_*` env var (코드 + doc + 테스트) → `KEBAB_*`. apply_env
  prefix 매칭 + 30+ 개 setting 키 모두.
- XDG paths: `~/.config/kb` / `~/.local/share/kb` / `~/.cache/kb` /
  `~/.local/state/kb` → `~/.config/kebab` 등. config defaults +
  expand_path tests + paths.rs 의 hardcode 모두.
- SQLite filename: `kb.sqlite` → `kebab.sqlite` (`SQLITE_FILE` const
  + 테스트 hardcode 모두).
- tracing target: `target: "kb-*"` → `"kebab-*"` (10+ 곳).
- snapshot fixture: `.kbignore` → `.kebabignore` (`fixtures/source-fs/
  tree-1.snapshot.json` 갱신).

## 검증

- `cargo test --workspace -j 1` clean (linker OOM 회피 위해 직렬).
- `cargo clippy --workspace --all-targets -- -D warnings` clean.

다음 commit 에서 docs sweep.

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

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

crates/kebab-app/src/lib.rs

@@ -61,7 +61,7 @@ pub use app::App;
 /// Kept in lock-step with the literal used in the `kb-store-sqlite`
 /// idempotency / round-trip tests so the version label written by the
 /// app and the one used in cross-crate fixtures match.
-const KB_PARSE_MD_VERSION: &str = "pulldown-cmark-0.x";
+const KEBAB_PARSE_MD_VERSION: &str = "pulldown-cmark-0.x";
 
 /// Caller-supplied knobs for one [`ask`] invocation.
 ///
@@ -187,7 +187,7 @@ pub fn ingest_with_config(
             .context("kb-app::ingest: ensure Lance table")?;
     }
 
-    let parser_version = ParserVersion(KB_PARSE_MD_VERSION.to_string());
+    let parser_version = ParserVersion(KEBAB_PARSE_MD_VERSION.to_string());
     let chunk_policy = chunk_policy_from_config(&app.config);
 
     // Pre-load every existing doc_id so we can label `IngestItem.kind`
@@ -236,7 +236,7 @@ pub fn ingest_with_config(
             Ok(i) => i,
             Err(e) => {
                 tracing::error!(
-                    target: "kb-app",
+                    target: "kebab-app",
                     path = %asset.workspace_path.0,
                     error = %e,
                     "kb-app::ingest: per-file fatal"
@@ -318,7 +318,7 @@ pub fn ingest_with_config(
                 progress,
             ) {
                 tracing::warn!(
-                    target: "kb-app",
+                    target: "kebab-app",
                     error = %e,
                     "kb-app::ingest: JobRepo::update_progress failed"
                 );
@@ -330,7 +330,7 @@ pub fn ingest_with_config(
                 None,
             ) {
                 tracing::warn!(
-                    target: "kb-app",
+                    target: "kebab-app",
                     error = %e,
                     "kb-app::ingest: JobRepo::finish failed"
                 );
@@ -338,7 +338,7 @@ pub fn ingest_with_config(
         }
         Err(e) => {
             tracing::warn!(
-                target: "kb-app",
+                target: "kebab-app",
                 error = %e,
                 "kb-app::ingest: JobRepo::create failed; run not recorded in `jobs`"
             );
@@ -361,7 +361,7 @@ pub fn ingest_with_config(
             Ok(s) => Some(s),
             Err(e) => {
                 tracing::warn!(
-                    target: "kb-app",
+                    target: "kebab-app",
                     error = %e,
                     "kb-app::ingest: failed to serialize items_json; storing NULL"
                 );
@@ -385,14 +385,14 @@ pub fn ingest_with_config(
     };
     if let Err(e) = app.sqlite.record_ingest_run(&row) {
         tracing::warn!(
-            target: "kb-app",
+            target: "kebab-app",
             error = %e,
             "kb-app::ingest: record_ingest_run failed"
         );
     }
 
     tracing::info!(
-        target: "kb-app",
+        target: "kebab-app",
         scanned = scanned_count,
         new = new_count,
         updated = updated_count,
@@ -448,7 +448,7 @@ fn ingest_one_asset(
     existing_doc_ids: &std::collections::HashSet<String>,
 ) -> anyhow::Result<kebab_core::IngestItem> {
     tracing::debug!(
-        target: "kb-app::ingest",
+        target: "kebab-app::ingest",
         path = %asset.workspace_path.0,
         "processing asset"
     );
@@ -795,7 +795,7 @@ pub fn doctor_with_config_path(config_path: Option<&std::path::Path>) -> anyhow:
 
     // data_dir_writable — probe the resolved storage.data_dir from the
     // loaded config when present, else the XDG default. Apply env
-    // overrides so KB_STORAGE_DATA_DIR is respected too.
+    // overrides so KEBAB_STORAGE_DATA_DIR is respected too.
     let data_dir = match loaded_cfg.as_ref() {
         Some(c) => {
             // Re-apply env overrides on top so the same precedence as

crates/kebab-app/src/logging.rs

@@ -1,6 +1,6 @@
 //! Tracing initialization helper for `kb-cli`.
 //!
-//! Daily-rolling file appender at `~/.local/state/kb/logs/` per task spec.
+//! Daily-rolling file appender at `~/.local/state/kebab/logs/` per task spec.
 //! Returns a `WorkerGuard` that the caller must keep alive until program
 //! exit (so buffered log lines flush).
 

crates/kebab-app/tests/ingest_lexical.rs

@@ -87,8 +87,8 @@ fn ingest_records_ingest_runs_row_with_aggregate_counts() {
     assert_eq!(report.scanned, 3);
 
     let db_path = std::path::PathBuf::from(&env.config.storage.data_dir)
-        .join("kb.sqlite");
-    let conn = rusqlite::Connection::open(&db_path).expect("open kb.sqlite");
+        .join("kebab.sqlite");
+    let conn = rusqlite::Connection::open(&db_path).expect("open kebab.sqlite");
     let (scanned, new_c, updated, skipped, errors, items_json): (
         i64,
         i64,