Increase mypy coverage and fixes

[NickM-27]

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Proposed change

Increase coverage of mypy to more modules and fix typing errors

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New feature
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code
• Documentation Update

AI disclosure

• No AI tools were used in this PR.
• AI tools were used in this PR. Details below:

AI tool(s) used (e.g., Claude, Copilot, ChatGPT, Cursor):

How AI was used (e.g., code generation, code review, debugging, documentation):

Extent of AI involvement (e.g., generated entire implementation, assisted with specific functions, suggested fixes):

Human oversight: Describe what manual review, testing, and validation you performed on the AI-generated portions.

Checklist

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
• I can explain every line of code in this PR if asked.
• UI changes including text have used i18n keys and have been added to the en locale.
• The code has been formatted using Ruff (ruff format frigate)