chore: import upstream snapshot with attribution

internal/eval/stdbench/testdata/coir/corpus.jsonl

@@ -0,0 +1,3 @@
+{"_id":"d1","title":"binary search","text":"func binarySearch(a []int, x int) int finds an element in a sorted slice"}
+{"_id":"d2","title":"quick sort","text":"func quickSort(a []int) sorts a slice in place"}
+{"_id":"d3","title":"hash map lookup","text":"func (m *HashMap) Get(key string) any returns the value stored under key"}

internal/eval/stdbench/testdata/coir/qrels/test.tsv

@@ -0,0 +1,3 @@
+query-id	corpus-id	score
+q1	d1	2
+q2	d3	1

internal/eval/stdbench/testdata/coir/queries.jsonl

@@ -0,0 +1,3 @@
+{"_id":"q1","text":"search a sorted array for an element"}
+{"_id":"q2","text":"look up a value in a map by its key"}
+{"_id":"q3","text":"a query with no relevance judgement"}

internal/eval/stdbench/testdata/contextbench.jsonl

@@ -0,0 +1,2 @@
+{"id":"t1","query":"parse the authentication token from a request","relevant":["c1"],"candidates":[{"id":"c1","text":"func parseAuthToken(req Request) Token validates and decodes the bearer token"},{"id":"c2","text":"func renderTemplate(name string, data any) string expands an HTML template"}]}
+{"id":"t2","query":"render an HTML template with data","relevant":[{"id":"c2","score":3}],"candidates":[{"id":"c1","text":"func parseAuthToken(req Request) Token validates and decodes the bearer token"},{"id":"c2","text":"func renderTemplate(name string, data any) string expands an HTML template"}]}