feat(Algebra/Lie/Sl2): add lemma exists_primitiveVector

[pion2024]

split 2 for the PR #37010

[github-actions]

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[github-actions]

PR summary b446ba6ef7

Import changes exceeding 2%

%	File
+24.71%	Mathlib.Algebra.Lie.Sl2

Import changes for modified files

Dependency changes

File	Base Count	Head Count	Change
Mathlib.Algebra.Lie.Sl2	1469	1832	+363 (+24.71%)

Import changes for all files

Files	Import difference
Mathlib.Algebra.Lie.Sl2	363

---

Declarations diff

+ IsTriangularizable.exists_hasEigenvalue
+ exists_hasPrimitiveVectorWith

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.

You can run this locally as

./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).

[ocfnash]

Thanks, I'll return once you've had a chance to consider my initial suggestions.

[pion2024]

Thanks, I'll return once you've had a chance to consider my initial suggestions.

Thanks, I've applied your suggestions.

[ocfnash]

@pion2024 Sorry I've been slow to return: I'll prioritise this next week.

[pion2024]

@pion2024 Sorry I've been slow to return: I'll prioritise this next week.

No worries, please take your time as I am actually a bit tied up myself. I'll still do my best to address your feedback as soon as I can.