Update mypy to the latest 2.3

[linsword13]

Also fix up typing issues reported by the new version.

[gemini-code-assist]

Code Review

This pull request adds type annotations to various command and utility modules in the Ramble codebase, typing dictionaries and lists that hold command formatters, subcommands, arguments, strategies, and modules. It also updates the pinned version of mypy in requirements-pinned.txt. However, the reviewer noted that mypy version 2.3.0 does not exist on PyPI, which will cause installation failures, and suggested pinning to a valid 1.x version instead.

[ramble-pr-bot]

Ramble Performance Test Metrics

Results produced with commit: b10987d

Test Name	Outcome	Duration (s)	Most Recent Run (s)	Last 5 Avg (s)
test_analyze_large_file	passed	2.9058	3.0625 (48760fd)	2.9483
test_large_template_expansion	passed	2.1314	2.1499 (48760fd)	2.1608
test_many_experiments	passed	38.4935	37.8478 (48760fd)	37.3594
test_many_objects_defaults	passed	21.3736	20.1824 (48760fd)	19.9687
test_matrix_filter_perf	passed	1.6224	1.6450 (48760fd)	1.6015

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.31%. Comparing base (48760fd) to head (b10987d).

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #1656   +/-   ##
========================================
  Coverage    93.31%   93.31%           
========================================
  Files          353      353           
  Lines        34334    34342    +8     
========================================
+ Hits         32039    32047    +8     
  Misses        2295     2295           

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