implement rolling hyper-log-log algorithm (#8068)

## Problem

See #7466

## Summary of changes

Implement algorithm descried in
https://hal.science/hal-00465313/document

Now new GUC is added:
`neon.wss_max_duration` which specifies size of sliding window (in
seconds). Default value is 1 hour.

It is possible to request estimation of working set sizes (within this
window using new function
`approximate_working_set_size_seconds`. Old function
`approximate_working_set_size` is preserved for backward compatibility.
But its scope is also limited by `neon.wss_max_duration`.

Version of Neon extension is changed to 1.4

## Checklist before requesting a review

- [ ] I have performed a self-review of my code.
- [ ] If it is a core feature, I have added thorough tests.
- [ ] Do we need to implement analytics? if so did you add the relevant
metrics to the dashboard?
- [ ] If this PR requires public announcement, mark it with
/release-notes label and add several sentences in this section.

## Checklist before merging

- [ ] Do not forget to reformat commit message to not include the above
checklist

---------

Co-authored-by: Konstantin Knizhnik <knizhnik@neon.tech>
Co-authored-by: Matthias van de Meent <matthias@neon.tech>

test_runner/regress/test_lfc_working_set_approximation.py

@@ -1,3 +1,4 @@
+import time
 from pathlib import Path
 
 from fixtures.log_helper import log
@@ -72,3 +73,46 @@ WITH (fillfactor='100');
     blocks = query_scalar(cur, "select approximate_working_set_size(true)")
     log.info(f"working set size after some index access of a few select pages only {blocks}")
     assert blocks < 10
+
+
+def test_sliding_working_set_approximation(neon_simple_env: NeonEnv):
+    env = neon_simple_env
+
+    endpoint = env.endpoints.create_start(
+        branch_name="main",
+        config_lines=[
+            "autovacuum = off",
+            "shared_buffers=1MB",
+            "neon.max_file_cache_size=256MB",
+            "neon.file_cache_size_limit=245MB",
+        ],
+    )
+    conn = endpoint.connect()
+    cur = conn.cursor()
+    cur.execute("create extension neon version '1.4'")
+    cur.execute(
+        "create table t(pk integer primary key, count integer default 0, payload text default repeat('?', 128))"
+    )
+    cur.execute("insert into t (pk) values (generate_series(1,1000000))")
+    time.sleep(2)
+    before_10k = time.monotonic()
+    cur.execute("select sum(count) from t where pk between 10000 and 20000")
+    time.sleep(2)
+    before_1k = time.monotonic()
+    cur.execute("select sum(count) from t where pk between 1000 and 2000")
+    after = time.monotonic()
+
+    cur.execute(f"select approximate_working_set_size_seconds({int(after - before_1k + 1)})")
+    estimation_1k = cur.fetchall()[0][0]
+    log.info(f"Working set size for selecting 1k records {estimation_1k}")
+
+    cur.execute(f"select approximate_working_set_size_seconds({int(after - before_10k + 1)})")
+    estimation_10k = cur.fetchall()[0][0]
+    log.info(f"Working set size for selecting 10k records {estimation_10k}")
+
+    cur.execute("select pg_table_size('t')")
+    size = cur.fetchall()[0][0] // 8192
+    log.info(f"Table size {size} blocks")
+
+    assert estimation_1k >= 20 and estimation_1k <= 40
+    assert estimation_10k >= 200 and estimation_10k <= 400

test_runner/regress/test_neon_extension.py

@@ -50,7 +50,7 @@ def test_neon_extension_compatibility(neon_env_builder: NeonEnvBuilder):
             # Ensure that the default version is also updated in the neon.control file
             assert cur.fetchone() == ("1.3",)
             cur.execute("SELECT * from neon.NEON_STAT_FILE_CACHE")
-            all_versions = ["1.3", "1.2", "1.1", "1.0"]
+            all_versions = ["1.4", "1.3", "1.2", "1.1", "1.0"]
             current_version = "1.3"
             for idx, begin_version in enumerate(all_versions):
                 for target_version in all_versions[idx + 1 :]: