Bump version to 1.1.6; fix storage bugs, tests, CI pipeline and Docker config

Storage fixes:
- Fix bloom filter hash2 OverflowDefect (uint64 instead of int Hash)
- Fix MemTable.put size calculation on overwrite (was leaking size)
- Fix fuzz_test duplicate-key issues in LSM delete and SSTable tests

Test fixes:
- Fix stress_test.nim: replace deprecated threadpool with std/threads
- Fix fuzz_test.nim: add missing imports (tables, algorithm, sets)
- Fix fuzz_test.nim: var sst for close() compatibility
- Remove unused imports from test_all.nim and bench_all.nim

Docker / CI fixes:
- Fix Dockerfile.source: invalid nimlang/nim:2.2.10-alpine tag → 2.2.10 + ubuntu:24.04 runtime
- Fix Dockerfile.source healthcheck (--spider → -qO- for 200 OK)
- Fix Dockerfile run comment ports (9470/9471 → 9912/9913)
- Fix scripts/docker-run.sh healthcheck port (9470 → 9912)
- Add ARG BUILD_DATE/VCS_REF to Dockerfile for docker-build.sh
- Update all version strings 1.1.4 → 1.1.6 across nimble/docker/source/docs

src/barabadb/storage/bloom.nim

@@ -24,10 +24,10 @@ proc hash1*(bf: BloomFilter, data: openArray[byte]): uint64 =
   result = uint64(!$h)
 
 proc hash2*(bf: BloomFilter, data: openArray[byte]): uint64 =
-  var h: Hash = 5381
+  var h: uint64 = 5381
   for b in data:
-    h = ((h shl 5) + h) + Hash(b)
-  result = uint64(h)
+    h = ((h shl 5) + h) + uint64(b)
+  result = h
 
 proc getHashes(bf: BloomFilter, data: openArray[byte]): seq[int] =
   let h1 = bf.hash1(data)

src/barabadb/storage/lsm.nim

@@ -68,15 +68,17 @@ proc put*(mt: var MemTable, key: string, value: seq[byte], timestamp: uint64, de
   let entrySize = key.len + value.len + 16
   if entrySize > mt.maxSize:
     return false
-  if mt.size + entrySize > mt.maxSize and mt.entries.len > 0:
-    return false
   let entry = Entry(key: key, value: value, timestamp: timestamp, deleted: deleted)
   let pos = mt.entries.lowerBound(entry, proc(a, b: Entry): int = cmp(a.key, b.key))
   if pos < mt.entries.len and mt.entries[pos].key == key:
+    let oldSize = mt.entries[pos].key.len + mt.entries[pos].value.len + 16
     mt.entries[pos] = entry
+    mt.size += entrySize - oldSize
   else:
+    if mt.size + entrySize > mt.maxSize and mt.entries.len > 0:
+      return false
     mt.entries.insert(entry, pos)
-  mt.size += entrySize
+    mt.size += entrySize
   return true
 
 proc get*(mt: MemTable, key: string): (bool, Entry) =