Apply DUNE-DAQ style guide: modernize type aliases and namespace syntax

[Copilot]

Description

Comprehensive style guide compliance review identified minor deviations from dune-daq/styleguide standards across header files.

Changes

Type aliases (§7.7): Replaced C-style typedef with modern using declarations in 10 header files:

// Before
typedef uint32_t word_t;

// After
using word_t = uint32_t;

Namespace syntax (§4.1): Updated to C++17 compact form in DAPHNEFrame.hpp:

// Before
namespace dunedaq {
namespace fddetdataformats {

// After
namespace dunedaq::fddetdataformats {

Formatting: Fixed spacing inconsistencies around assignment operators and replaced tabs with spaces.

Type of change

• Documentation (non-breaking change that adds or improves the documentation)
• New feature or enhancement (non-breaking change which adds functionality)
• Optimization (non-breaking change that improves code/performance)
• Bug fix (non-breaking change which fixes an issue)
• Breaking change (whatever its nature)

Testing checklist

• Unit tests pass (e.g. dbt-build --unittest)
• Minimal system quicktest passes (pytest -s minimal_system_quick_test.py)
• Full set of integration tests pass (daqsystemtest_integtest_bundle.sh)
• Python tests pass if applicable (e.g. python -m pytest)
• Pre-commit hooks run successfully if applicable (e.g. pre-commit run --all-files)

Header-only style changes. Syntax validation confirms correctness. No functional changes.

Further checks

• Code is commented where needed, particularly in hard-to-understand areas
• Code style is correct (dbt-build --lint, and/or see https://dune-daq-sw.readthedocs.io/en/latest/packages/styleguide/)
• If applicable, new tests have been added or an issue has been opened to tackle that in the future.

Original prompt

review code in this repo using dune-daq/styleguide

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[jcfreeman2]

LGTM; one less thing to mention for the fddetdataformats code review.