refactor(embed): candle provider/crate 제거 — fastembed+ollama로 충분

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012Mc6W1fgsrbFKTsqA6P8La

crates/kebab-cli/Cargo.toml

@@ -51,10 +51,5 @@ tempfile     = { workspace = true }
 rusqlite     = { workspace = true }
 time         = { workspace = true }
 
-[features]
-# opt-in (macOS): build the `kebab` binary with candle on the Apple Silicon GPU.
-#   cargo build --release --features embed_metal
-embed_metal = ["kebab-app/embed_metal"]
-
 [lints]
 workspace = true