refactor(Analysis): golf Mathlib/Analysis/Convex/Between

[yuanyi-350]

• rewrites Wbtw.sameRay_vsub via sameRay_of_mem_segment
• rewrites Wbtw.collinear via collinear_insert_of_mem_affineSpan_pair
• simplifies wbtw_iff_sameRay_vsub to a simp proof using segment lemmas

Extracted from #37968

[github-actions]

PR summary 1c558eb49a

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

---

Declarations diff

No declarations were harmed in the making of this PR! 🐙

You can run this locally as follows

## summary with just the declaration names:
./scripts/pr_summary/declarations_diff.sh <optional_commit>

## more verbose report:
./scripts/pr_summary/declarations_diff.sh long <optional_commit>

The doc-module for scripts/pr_summary/declarations_diff.sh contains some details about this script.

---

No changes to technical debt.

This script lives in the mathlib-ci repository. To run it locally, from your mathlib4 directory:

git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci
../mathlib-ci/scripts/reporting/technical-debt-metrics.sh pr_summary

• The relative value is the weighted sum of the differences with weight given by the inverse of the current value of the statistic.
• The absolute value is the relative value divided by the total sum of the inverses of the current values (i.e. the weighted average of the differences).

[yuanyi-350]

I ran a profiler comparison for the changed declarations in this PR.

Results (seconds):

• Wbtw.sameRay_vsub: 0.549536 -> 0.061617 (-88.79%)
• Wbtw.collinear: 0.121434 -> 0.020693 (-82.96%)
• wbtw_iff_sameRay_vsub: 0.643571 -> 0.021504 (-96.66%)

Overall:

• All measured changed declarations are faster after this refactor.

[grunweg]

Why do you need insert_comm here?