hrw4u: Add support for += / add-header

[zwoop]

This also cleans up the maps.py Maps definitions, including moving most of the parameter values into a type class. This makes for more readable code, even though it adds a bit additional code.

[Copilot]

Pull Request Overview

This PR adds support for the += operator (add-header functionality) in hrw4u and refactors the table definitions to use a type-safe MapParams class instead of tuples. The changes improve code readability and maintainability while extending the language's capabilities.

Key changes:

• Introduces += operator for adding headers to existing header values
• Replaces tuple-based table definitions with MapParams type class for better code clarity
• Updates grammar to support PLUSEQUAL token

Reviewed Changes

Copilot reviewed 20 out of 21 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
tools/hrw4u/grammar/hrw4u.g4	Adds PLUSEQUAL token and statement rule for += operator
tools/hrw4u/src/types.py	Defines new MapParams class and ADD_HEADER magic string
tools/hrw4u/src/visitor.py	Implements handling for += assignments
tools/hrw4u/src/tables.py	Refactors all table definitions to use MapParams instead of tuples
tools/hrw4u/src/symbols.py	Updates symbol resolution logic for new MapParams structure and adds += support
tools/hrw4u/src/symbols_base.py	Updates type signatures to use MapParams
tools/hrw4u/src/hrw_symbols.py	Adapts reverse symbol resolution for MapParams and add-header
tools/hrw4u/src/common.py	Adds ADD_OPERATION constant
tools/hrw4u/src/suggestions.py	Updates suggestion logic for MapParams
tools/hrw4u/src/lsp/*.py	Updates LSP features (hover, completions) for MapParams
tools/hrw4u/src/kg_visitor.py	Updates knowledge graph generation for MapParams
tools/hrw4u/src/generators.py	Updates reverse mapping generators for MapParams
tools/hrw4u/tests/data/hooks/remap.*	Test data for += operator usage
tools/hrw4u/tests/data/ops/*	Test data updates for QSA and boolean handling
doc/admin-guide/configuration/hrw4u.en.rst	Documentation for += operator usage

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[zwoop]

I resolved the nitpick comments from CoPilot.

[cmcfarlen]

seems cool