QuestDB 6.0.4 July release, Prometheus metrics support

The latest QuestDB release, version 6.0.4, introduces enhancements driven by community feedback, including performance improvements, increased parallelization, and the introduction of a framework for Prometheus metrics, developed by community member Piotr Rżysko. This update addresses stability issues and provides new capabilities such as calendar alignment for SAMPLE BY queries, allowing sampled groups to align with calendar dates using optional time zones and offsets. The release also optimizes SQL query performance, particularly for LATEST BY queries, by parallelizing operations and refining aggregate calculations. Prometheus metrics have been integrated, enabling users to monitor QuestDB instances by setting basic counters for SQL queries. A notable change is the enforcement of timestamps having only positive values, disallowing pre-1970 dates. The release is available on Docker Hub, and QuestDB is encouraging community engagement through GitHub discussions to gather feedback and foster open-ended conversations.