Record full Google CPU routing regression with independently verified scores

docs/RETRIEVAL-ROUTING.md

@@ -1,10 +1,10 @@
 # Mixed query routing audit
 
 Read-only implementation audit, 2026-10-13, source revision `5d9cfc4`.
-These findings describe current behavior; they are not a retrieval-quality
+These opening findings describe that pre-fix snapshot; they are not a retrieval-quality
 measurement or an implemented ranking change.
 
-## Current behavior
+## Pre-fix behavior at 5d9cfc4
 
 `HybridSearch::query_vector` selects Google's CodeRetrieval task only when
 `SearchOptions::code_only` is true. All-files searches use the general task,
@@ -14,7 +14,7 @@ accidentally. See `crates/searchi-service/src/lib.rs`.
 
 The audio preference in `crates/searchi-service/src/routing.rs` recognizes words
 such as speech, sound and music. Document and image cues veto that preference;
-code cues currently do not. If the preferred audio search returns any qualifying
+code cues did not at this snapshot. If the preferred audio search returns any qualifying
 candidate, it becomes the exclusive semantic lane. Consequently a query such as
 "code that detects speech" can exclude semantic code candidates in All files.
 Lexical candidates still participate in hybrid fusion, and explicit Code scope
@@ -72,6 +72,10 @@ diagnostic lane. Updated default semantic routing also returned the source
 implementation, proving the exclusive suppression is removed in this fixture.
 The test asserts candidate preservation, not top-1 superiority or broad quality.
 The full mixed baseline above remains the unchanged pre-fix measurement.
+The completed [0.1.4 full regression](MIXED-QUALITY-0.1.4.md) now confirms that
+this known failed query returns the implementation first. Code intents in All
+files improved from 10/14 to 11/14 top-1 and 13/14 to 14/14 recall@5, without
+scored regression elsewhere. Independent relevance and no-answer gates stay open.
 
 With this fix and the verified-asset callback, the Windows CPU workspace suite
 passed 130 tests (23 explicitly ignored integration/resource checks), desktop