feat: DuckDB quantiles in-process (gcc CGO), not Ladybug. (#34)

OQ3: internal/duckstats + bin/qa/stats.go. Zig stays Ladybug-only.
mikefarah/yq for small structured slices. Gitea #30.

skills/web-search/SKILL.md

@@ -11,7 +11,7 @@ description: >-
 ```bash
 bin/web/search.go "LadybugDB vector index"
 bin/web/search.go "model2vec multilingual" --category it
-bin/web/search.go "hypervisor" --site example.com --json | jq -r '.results[].url'
+bin/web/search.go "hypervisor" --site example.com --json | yq -r '.results[].url'
 bin/web/search.go "postgres partial index" --lang en --fresh year
 ```
 

skills/web-search/reference/instance-tuning.md

@@ -43,7 +43,7 @@ found" unless the client refuses to call it absence.
 
 ```bash
 for i in $(seq 10); do
-  bin/web/search.go "test $i" -n 1 --refresh --json | jq -r .status
+  bin/web/search.go "test $i" -n 1 --refresh --json | yq -r '.status'
 done
 ```