feat(store): fetch contributions incrementally and persist history in SQLite

Bound each provider's startFetch()/resolveFetch() to an optional
since/until window, wire a SQLite-backed ContributionStore into
ContributionAggregator (fetch only the trailing window past the last
stored date, merge into the store, prune by CONTRIBUTIONS_RETENTION_DAYS),
and add a graph:contributions:refetch command to force a full or ranged
re-fetch in <=365-day chunks. This is the root fix for the full
365-day-refetch timeout that used to hit on every cache miss.

tests/Unit/Service/Provider/GitHubProviderTest.php

@@ -29,6 +29,7 @@ final class GitHubProviderTest extends TestCase
         );
     }
 
+    /** @param array<int, array{contributionDays: array<int, array{date: string, contributionCount: int}>}> $weeks */
     private function stubGraphqlResponse(array $weeks): ResponseInterface
     {
         $response = $this->createStub(ResponseInterface::class);
@@ -131,4 +132,27 @@ final class GitHubProviderTest extends TestCase
 
         $this->assertSame([], $result);
     }
+
+    #[Test]
+    public function it_narrows_the_graphql_query_window_when_since_and_until_are_given(): void
+    {
+        $since = new \DateTimeImmutable('2024-01-01');
+        $until = new \DateTimeImmutable('2024-01-31');
+        $capturedQuery = null;
+
+        $client = $this->createMock(HttpClientInterface::class);
+        $client->method('request')->willReturnCallback(
+            function (string $method, string $url, array $options) use (&$capturedQuery): ResponseInterface {
+                $capturedQuery = $options['json']['query'];
+
+                return $this->stubGraphqlResponse([]);
+            }
+        );
+
+        $provider = $this->makeProvider(client: $client);
+        $provider->startFetch($since, $until);
+
+        $this->assertStringContainsString('2024-01-01T00:00:00Z', $capturedQuery);
+        $this->assertStringContainsString('2024-01-31T23:59:59Z', $capturedQuery);
+    }
 }