[priyam0k]

Summary of Changes

• Centralizes axis order tuples and lookup mappings in utility_functions and re-exports in core.typing.
• Migrates origin and development to TriangleAxis descriptors, retiring separate internal dimension storage into _axes.
• Implements Triangle._set_axis to generalize dimension validation and assignment.
• Adds TrianglePandas._get_axis_number and routes _get_axis to eliminate redundant local lookup dicts.
• Adds comprehensive unit tests for _set_axis and legacy pickle unpickling.

Related GitHub Issue(s)

Closes #1053

AI/LLM Usage

Used basic model for initial unit test drafting and lint checks.

Additional Context for Reviewers

Follow-up to Issue #1053, stacked directly on top of #1304 (Stack #1437). Can be reviewed here and retargeted to main once Stack #1437 finishes merging.

Submitter's Checklist

• I have reviewed and am adhering to the standards outlined in the project Governing Doc.
• The PR subject title summarizes the changes, with one proper prefix ([FIX], [FEAT], [DOCS], [TST], [CHORE], or [BRK]).
• I am a human (not a bot), and this PR form is written by a human.

Reviewer's Checklist

• The implementation addresses the associated issue(s).
• The implementation is appropriate, maintainable, and follows ARCHITECTURE.md.
• PR subject title has the proper prefix and the subject is appropriate.
• Relevant issue(s) are linked.
• AI/LLM usage is disclosed and appropriate.
• Documentation and tests are appropriate.
• CI tests passed, or any failures are acceptable.
• Leave a comment with the final recommendation (e.g. approve as is, request a secondary review, or flag an area for more review).

---

Note

Medium Risk
Touches core Triangle axis storage, assignment, and unpickling paths; regressions could affect slicing, I/O, and pandas-like axis APIs despite added tests.

Overview
Centralizes Triangle axis metadata in utility_functions (_axis_orders, name/number lookups) and re-exports it from core.typing, so pandas helpers and descriptors share one mapping instead of local dicts.

Unifies dimension storage behind TriangleAxis for all four axes: origin and development join index/columns with getters/setters and raw values in _axes, while legacy _odims/_ddims (and pickle __setstate__) still populate that store. Triangle._set_axis validates and assigns any axis by int or name; TrianglePandas._get_axis_number delegates to the shared helpers.

Adds unit tests for _set_axis, origin/development edge cases, and redundant legacy pickle state.

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[github-actions]

Pyright Type Completeness

View the full pyright --verifytypes output for this commit

Project (full chainladder package, at this PR's head): 15.9% of exported symbols fully typed (241 / 1519)

	Known	Ambiguous	Unknown	Total
Project (head)	241	106	1172	1519

Other symbols referenced but not exported by chainladder: 13

	Known	Ambiguous	Unknown	Total
Other (head)	3	1	9	13

Symbols without documentation:

• Functions without docstring: 342
• Functions without default param: 0
• Classes without docstring: 8

Patch (exported symbols added or changed by this PR): 50.0% fully typed (2 / 4)

	Known	Ambiguous	Unknown	Total
Patch	2	0	2	4

Patch symbol details

Symbol	Status	Change
chainladder.core.tests.test_triangle.test_centralized_axis_edge_cases	❌ unknown	new
chainladder.core.tests.test_triangle.test_set_axis	❌ unknown	new
chainladder.core.triangle.Triangle.development	✅ known	changed (was ❌ unknown)
chainladder.core.triangle.Triangle.origin	✅ known	changed (was ❌ unknown)

[codecov]

Codecov Report

❌ Patch coverage is 94.49541% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 94.32%. Comparing base (6dcecb4) to head (03be78d).

Files with missing lines	Patch %	Lines
chainladder/core/triangle.py	90.24%	2 Missing and 2 partials ⚠️
chainladder/core/axis.py	94.73%	0 Missing and 2 partials ⚠️

Additional details and impacted files

@@                       Coverage Diff                       @@
##           feature/deprecate-date-dims    #1454      +/-   ##
===============================================================
- Coverage                        94.33%   94.32%   -0.01%     
===============================================================
  Files                               97       97              
  Lines                             6157     6221      +64     
  Branches                           801      813      +12     
===============================================================
+ Hits                              5808     5868      +60     
- Misses                             224      225       +1     
- Partials                           125      128       +3     

Flag	Coverage Δ
unittests	94.32% <94.49%> (-0.01%)	⬇️

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[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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