Additions for 8.2.2

[goodroot]

This pull request includes multiple changes to the documentation files, mainly focusing on adding new configuration options, enhancing existing documentation, and optimizing SQL functions. The most important changes are summarized below:

New Configuration Options:

• Added new context paths for various HTTP services in documentation/configuration-utils/_http.config.json. These include paths for the Web Console, file import, table status, SQL execution, and others.
• Introduced a new log.timezone configuration in documentation/configuration-utils/_log.config.json to set the timezone for log timestamps.

Documentation Enhancements:

• Added an option to log malformed ILP messages in documentation/configuration.md.
• Enhanced the dateadd function documentation in documentation/reference/function/date-time.md to include a timezone parameter for DST-aware calculations. [1] [2] [3]
• Added a section on optimization with WHERE clauses in documentation/reference/function/timestamp.md to explain how QuestDB optimizes queries involving designated timestamp columns.

SQL Function Updates:

• Introduced the first_not_null_value() window function in documentation/reference/function/window.md to return the first non-null value in a set of rows defined by the window frame.
• Added an example of adding a column only if it doesn't already exist in documentation/reference/sql/alter-table-add-column.md.

Miscellaneous:

• Updated the union-except-intersect documentation to include an example of combining IPv4 columns with VARCHAR/STRING columns using implicit casting. [1] [2]

[github-actions]

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