chore: workspace-wide cleanup — clippy::pedantic baseline + auto-fix

cut PR v0.18.0 전 마지막 정리. 사용자 요청: "전체 코드베이스를 깔끔하고 알아보기 쉽게".

## Workspace lints

- `Cargo.toml` 의 `[workspace.lints.clippy]` 에 `pedantic = "warn"` (priority -1) + 의도적 allow-list 추가:
  - cast_possible_truncation / cast_possible_wrap / cast_sign_loss / cast_precision_loss — ONNX i64 / hash modular reduction 등 의도적 truncation.
  - doc_markdown / missing_errors_doc / missing_panics_doc — cosmetic doc style.
  - too_many_lines / module_name_repetitions / must_use_candidate / needless_pass_by_value / manual_let_else / items_after_statements / similar_names — informational only.
  - format_collect / match_wildcard_for_single_variants / trivially_copy_pass_by_ref / unnecessary_wraps — intentional patterns (exhaustive match, future Result variants 등).
  - default_trait_access — `Foo::default()` 가 idiomatic.
  - float_cmp — NLI / RRF score 의 explicit threshold 비교 의도.
  - struct_excessive_bools / case_sensitive_file_extension_comparisons / naive_bytecount / ignore_without_reason — domain-specific 의도.
  - format_push_string / return_self_not_must_use / match_same_arms — builder / wire-label / hot-path 패턴 보존.
  - needless_continue / used_underscore_binding / nonminimal_bool / unreadable_literal / many_single_char_names / doc_link_with_quotes / assigning_clones / collapsible_str_replace / trivial_regex / elidable_lifetime_names / range_plus_one / explicit_iter_loop / implicit_hasher / ref_option — remaining low-value style.
- 각 24 crate `Cargo.toml` 에 `[lints] workspace = true` 추가.

## Auto-fix

`cargo clippy --workspace --all-targets --fix` 적용 — 128 files changed, 552 insertions / 472 deletions. 주로:
- uninlined_format_args (~18): `format!("{}", x)` → `format!("{x}")`.
- redundant_closure_for_method_calls (~33): `.map(|x| x.foo())` → `.map(T::foo)`.
- 그 외 mechanical refactor.

## 검증

- `cargo clippy --workspace --all-targets -j 1 -- -D warnings` clean (pedantic + 모든 lint group).
- `cargo test --workspace --no-fail-fast -j 1` — **1293 tests pass + 1 pre-existing flaky fail** (`kebab-mcp::tools_call_ask_multi_hop::ask_tool_routes_multi_hop_true_to_decompose_first`, HOTFIX candidate, cleanup 무관). 회귀 0.

Wire 영향: 없음.
Behavior 영향: 없음 (mechanical refactor only).

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

crates/kebab-store-vector/Cargo.toml

@@ -53,3 +53,6 @@ serde_json      = { workspace = true }
 # touch rusqlite directly (P3-3 spec: kb-store-vector must not list
 # rusqlite/globset as direct deps).
 rusqlite        = { workspace = true }
+
+[lints]
+workspace = true

crates/kebab-store-vector/src/arrow_batch.rs

@@ -189,8 +189,8 @@ mod tests {
 
     fn make_rec(chunk_idx: u8, dim: usize) -> VectorRecord {
         VectorRecord {
-            chunk_id: ChunkId(format!("{:032x}", chunk_idx)),
-            embedding_id: EmbeddingId(format!("{:032x}", 0xeeeeu16 + chunk_idx as u16)),
+            chunk_id: ChunkId(format!("{chunk_idx:032x}")),
+            embedding_id: EmbeddingId(format!("{:032x}", 0xeeeeu16 + u16::from(chunk_idx))),
             vector: vec![0.1_f32; dim],
             doc_id: DocumentId("aaaa".repeat(8)),
             text: format!("text-{chunk_idx}"),

crates/kebab-store-vector/src/store.rs

@@ -169,16 +169,13 @@ impl LanceVectorStore {
             arrow_schema::DataType::FixedSizeList(_, table_dim) => {
                 if (*table_dim as usize) != dim {
                     anyhow::bail!(
-                        "dimension mismatch: table has dim {}, records have dim {}",
-                        table_dim,
-                        dim
+                        "dimension mismatch: table has dim {table_dim}, records have dim {dim}"
                     );
                 }
                 Ok(())
             }
             other => anyhow::bail!(
-                "embedding column has unexpected Arrow type {:?}",
-                other
+                "embedding column has unexpected Arrow type {other:?}"
             ),
         }
     }
@@ -390,19 +387,15 @@ impl VectorStore for LanceVectorStore {
         // matching `query_vec.len()`. In v1 there's typically one
         // model in play; if there are several we pick the first match.
         let dim = query_vec.len();
-        let table_name = match self
+        let table_name = if let Some(name) = self
             .runtime
-            .block_on(async { find_matching_table(&self.connection, dim).await })?
-        {
-            Some(name) => name,
-            None => {
-                tracing::debug!(
-                    target: "kebab-store-vector",
-                    dim,
-                    "search: no Lance table matches query dim — returning empty"
-                );
-                return Ok(Vec::new());
-            }
+            .block_on(async { find_matching_table(&self.connection, dim).await })? { name } else {
+            tracing::debug!(
+                target: "kebab-store-vector",
+                dim,
+                "search: no Lance table matches query dim — returning empty"
+            );
+            return Ok(Vec::new());
         };
 
         // Pre-fetch 2*k Lance rows; we'll filter against SQLite
@@ -574,7 +567,7 @@ fn score_from_distance(distance: f32) -> f32 {
         return 0.0;
     }
     let sim = 1.0 - distance;
-    (sim + 1.0) / 2.0
+    f32::midpoint(sim, 1.0)
 }
 
 /// Find a Lance table whose embedding column is FixedSizeList<Float32, dim>.

crates/kebab-store-vector/tests/common/mod.rs

@@ -49,13 +49,11 @@ use std::sync::Arc;
 pub fn require_avx_or_panic() {
     #[cfg(target_arch = "x86_64")]
     {
-        if !std::is_x86_feature_detected!("avx") {
-            panic!(
-                "kb-store-vector integration test requires AVX-capable hardware; \
-                 host CPU lacks AVX. Run on an AVX-capable machine. \
-                 See crates/kb-store-vector/tests/common/mod.rs."
-            );
-        }
+        assert!(std::is_x86_feature_detected!("avx"), 
+            "kb-store-vector integration test requires AVX-capable hardware; \
+             host CPU lacks AVX. Run on an AVX-capable machine. \
+             See crates/kb-store-vector/tests/common/mod.rs."
+        );
     }
 }
 
@@ -167,17 +165,17 @@ pub fn make_record(
     model: &str,
 ) -> VectorRecord {
     let dim = vector.len();
-    let chunk_id = ChunkId(format!("{:032x}", 0x1100u32 + chunk_idx as u32));
-    let doc_id = DocumentId(format!("{:032x}", 0xd0c0u32 + doc_idx as u32));
+    let chunk_id = ChunkId(format!("{:032x}", 0x1100u32 + u32::from(chunk_idx)));
+    let doc_id = DocumentId(format!("{:032x}", 0xd0c0u32 + u32::from(doc_idx)));
     let embedding_id =
-        EmbeddingId(format!("{:032x}", 0xeeee0000u32 + chunk_idx as u32));
+        EmbeddingId(format!("{:032x}", 0xeeee0000u32 + u32::from(chunk_idx)));
     VectorRecord {
         chunk_id,
         embedding_id,
         vector,
         doc_id,
         text: text.to_string(),
-        heading_path: heading.iter().map(|s| s.to_string()).collect(),
+        heading_path: heading.iter().map(std::string::ToString::to_string).collect(),
         model_id: EmbeddingModelId(model.to_string()),
         model_version: EmbeddingVersion("v1".to_string()),
         dimensions: dim,

crates/kebab-store-vector/tests/snapshot.rs

@@ -93,14 +93,12 @@ fn vector_hits_snapshot_run_1() {
     // placeholder. The placeholder JSON carries a `_comment` field
     // with regeneration instructions; production fixtures (a captured
     // hits array) do not.
-    if expected.get("_comment").is_some() {
-        panic!(
-            "snapshot fixture is a placeholder — regenerate on AVX hardware then commit. \
-             Path: {}. To regenerate: \
-             `KEBAB_UPDATE_SNAPSHOTS=1 cargo test -p kb-store-vector -- --ignored snapshot`.",
-            fixture.display()
-        );
-    }
+    assert!(!expected.get("_comment").is_some(), 
+        "snapshot fixture is a placeholder — regenerate on AVX hardware then commit. \
+         Path: {}. To regenerate: \
+         `KEBAB_UPDATE_SNAPSHOTS=1 cargo test -p kb-store-vector -- --ignored snapshot`.",
+        fixture.display()
+    );
 
     assert_eq!(
         actual, expected,

crates/kebab-store-vector/tests/upsert_search.rs

@@ -67,7 +67,7 @@ fn upsert_ten_then_search_returns_five() {
         // for the rest, with small per-row jitter so they stay
         // distinct in the index.
         let mut v = if i < 5 { dir(0) } else { dir(1) };
-        v[3] = (i as f32) * 0.001;
+        v[3] = f32::from(i) * 0.001;
         let rec = make_record(i, i, v, &format!("text-{i}"), &["A"], MODEL);
         env.seed_chunk(
             &rec.chunk_id.0,
@@ -264,7 +264,7 @@ fn determinism_same_query_same_top_k() {
     let recs: Vec<_> = (0..6u8)
         .map(|i| {
             let mut v = dir(i % 4);
-            v[3] = (i as f32) * 0.001;
+            v[3] = f32::from(i) * 0.001;
             let rec = make_record(i, i, v, &format!("t-{i}"), &[], MODEL);
             env.seed_chunk(
                 &rec.chunk_id.0,