feat(bd-1ksf): wire hybrid search (FTS5 + vector + RRF) to CLI

Make run_search async, replace hardcoded lexical mode with SearchMode::parse(),
wire search_hybrid() with OllamaClient for semantic/hybrid modes, graceful
degradation when Ollama unavailable.

Closes: bd-1ksf

src/cli/commands/search.rs

@@ -1,3 +1,5 @@
+use std::collections::HashMap;
+
 use console::style;
 use serde::Serialize;
 
@@ -8,9 +10,10 @@ use crate::core::paths::get_db_path;
 use crate::core::project::resolve_project;
 use crate::core::time::{ms_to_iso, parse_since};
 use crate::documents::SourceType;
+use crate::embedding::ollama::{OllamaClient, OllamaConfig};
 use crate::search::{
-    FtsQueryMode, PathFilter, SearchFilters, apply_filters, get_result_snippet, rank_rrf,
-    search_fts,
+    FtsQueryMode, HybridResult, PathFilter, SearchFilters, SearchMode, get_result_snippet,
+    search_fts, search_hybrid,
 };
 
 #[derive(Debug, Serialize)]
@@ -58,7 +61,7 @@ pub struct SearchCliFilters {
     pub limit: usize,
 }
 
-pub fn run_search(
+pub async fn run_search(
     config: &Config,
     query: &str,
     cli_filters: SearchCliFilters,
@@ -71,15 +74,18 @@ pub fn run_search(
 
     let mut warnings: Vec<String> = Vec::new();
 
-    // Determine actual mode: vector search requires embeddings, which need async + Ollama.
-    // Until hybrid/semantic are wired up, we run lexical and warn if the user asked for more.
-    let actual_mode = "lexical";
-    if requested_mode != "lexical" {
-        warnings.push(format!(
-            "Requested mode '{}' is not yet available; falling back to lexical search.",
-            requested_mode
-        ));
-    }
+    let actual_mode = SearchMode::parse(requested_mode).unwrap_or(SearchMode::Hybrid);
+
+    let client = if actual_mode != SearchMode::Lexical {
+        let ollama_cfg = &config.embedding;
+        Some(OllamaClient::new(OllamaConfig {
+            base_url: ollama_cfg.base_url.clone(),
+            model: ollama_cfg.model.clone(),
+            ..OllamaConfig::default()
+        }))
+    } else {
+        None
+    };
 
     let doc_count: i64 = conn
         .query_row("SELECT COUNT(*) FROM documents", [], |row| row.get(0))
@@ -89,7 +95,7 @@ pub fn run_search(
         warnings.push("No documents indexed. Run 'lore generate-docs' first.".to_string());
         return Ok(SearchResponse {
             query: query.to_string(),
-            mode: actual_mode.to_string(),
+            mode: actual_mode.as_str().to_string(),
             total_results: 0,
             results: vec![],
             warnings,
@@ -151,52 +157,54 @@ pub fn run_search(
         limit: cli_filters.limit,
     };
 
-    let requested = filters.clamp_limit();
-    let top_k = if filters.has_any_filter() {
-        (requested * 50).clamp(200, 1500)
-    } else {
-        (requested * 10).clamp(50, 1500)
-    };
-
-    let fts_results = search_fts(&conn, query, top_k, fts_mode)?;
-    let fts_tuples: Vec<(i64, f64)> = fts_results
-        .iter()
-        .map(|r| (r.document_id, r.bm25_score))
-        .collect();
-
-    let snippet_map: std::collections::HashMap<i64, String> = fts_results
+    // Run FTS separately for snippet extraction (search_hybrid doesn't return snippets).
+    let snippet_top_k = filters
+        .clamp_limit()
+        .checked_mul(10)
+        .unwrap_or(500)
+        .clamp(50, 1500);
+    let fts_results = search_fts(&conn, query, snippet_top_k, fts_mode)?;
+    let snippet_map: HashMap<i64, String> = fts_results
         .iter()
         .map(|r| (r.document_id, r.snippet.clone()))
         .collect();
 
-    let ranked = rank_rrf(&[], &fts_tuples);
-    let ranked_ids: Vec<i64> = ranked.iter().map(|r| r.document_id).collect();
+    // search_hybrid handles recall sizing, RRF ranking, and filter application internally.
+    let (hybrid_results, mut hybrid_warnings) = search_hybrid(
+        &conn,
+        client.as_ref(),
+        query,
+        actual_mode,
+        &filters,
+        fts_mode,
+    )
+    .await?;
+    warnings.append(&mut hybrid_warnings);
 
-    let filtered_ids = apply_filters(&conn, &ranked_ids, &filters)?;
-
-    if filtered_ids.is_empty() {
+    if hybrid_results.is_empty() {
         return Ok(SearchResponse {
             query: query.to_string(),
-            mode: actual_mode.to_string(),
+            mode: actual_mode.as_str().to_string(),
             total_results: 0,
             results: vec![],
             warnings,
         });
     }
 
-    let hydrated = hydrate_results(&conn, &filtered_ids)?;
+    let ranked_ids: Vec<i64> = hybrid_results.iter().map(|r| r.document_id).collect();
+    let hydrated = hydrate_results(&conn, &ranked_ids)?;
 
-    let rrf_map: std::collections::HashMap<i64, &crate::search::RrfResult> =
-        ranked.iter().map(|r| (r.document_id, r)).collect();
+    let hybrid_map: HashMap<i64, &HybridResult> =
+        hybrid_results.iter().map(|r| (r.document_id, r)).collect();
 
     let mut results: Vec<SearchResultDisplay> = Vec::with_capacity(hydrated.len());
     for row in &hydrated {
-        let rrf = rrf_map.get(&row.document_id);
+        let hr = hybrid_map.get(&row.document_id);
         let fts_snippet = snippet_map.get(&row.document_id).map(|s| s.as_str());
         let snippet = get_result_snippet(fts_snippet, &row.content_text);
 
         let explain_data = if explain {
-            rrf.map(|r| ExplainData {
+            hr.map(|r| ExplainData {
                 vector_rank: r.vector_rank,
                 fts_rank: r.fts_rank,
                 rrf_score: r.rrf_score,
@@ -217,14 +225,14 @@ pub fn run_search(
             labels: row.labels.clone(),
             paths: row.paths.clone(),
             snippet,
-            score: rrf.map(|r| r.normalized_score).unwrap_or(0.0),
+            score: hr.map(|r| r.score).unwrap_or(0.0),
             explain: explain_data,
         });
     }
 
     Ok(SearchResponse {
         query: query.to_string(),
-        mode: actual_mode.to_string(),
+        mode: actual_mode.as_str().to_string(),
         total_results: results.len(),
         results,
         warnings,
@@ -360,8 +368,12 @@ pub fn print_search_results(response: &SearchResponse) {
 
         if let Some(ref explain) = result.explain {
             println!(
-                "    {} fts_rank={} rrf_score={:.6}",
+                "    {} vector_rank={} fts_rank={} rrf_score={:.6}",
                 style("[explain]").magenta(),
+                explain
+                    .vector_rank
+                    .map(|r| r.to_string())
+                    .unwrap_or_else(|| "-".into()),
                 explain
                     .fts_rank
                     .map(|r| r.to_string())

src/main.rs

@@ -1778,7 +1778,8 @@ async fn handle_search(
         fts_mode,
         &args.mode,
         explain,
-    )?;
+    )
+    .await?;
     let elapsed_ms = start.elapsed().as_millis() as u64;
 
     if robot_mode {