feat: tag Function.leftLim with to_dual

[EtienneC30]

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[github-actions]

PR summary e4213d57a1

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

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Declarations diff (regex)

- ContinuousWithinAt.rightLim_eq
- Function.rightLim
- Monotone.tendsto_nhdsGT
- MonotoneOn.tendsto_nhdsGT
- TFAE_mem_nhdsLE
- TFAE_mem_nhdsLT
- continuousWithinAt_rightLim_Ici
- countable_setOfPred_isolated_left
- countable_setOfPred_isolated_left_within
- mapClusterPt_rightLim
- mem_nhdsLE_iff_exists_Icc_subset
- mem_nhdsLE_iff_exists_Ioc_subset
- mem_nhdsLE_iff_exists_Ioc_subset'
- mem_nhdsLE_iff_exists_mem_Ico_Ioc_subset
- mem_nhdsLT_iff_exists_Ico_subset
- mem_nhdsLT_iff_exists_Ioo_subset
- mem_nhdsLT_iff_exists_Ioo_subset'
- mem_nhdsLT_iff_exists_mem_Ico_Ioo_subset
- nhdsLE_basis_Icc
- nhdsLT_basis
- nhdsLT_basis_Ico
- nhdsLT_basis_Ico_of_exists_lt
- nhdsLT_basis_of_exists_lt
- rightLim_eq_of_eq_bot
- rightLim_eq_of_isTop
- rightLim_eq_of_not_tendsto
- rightLim_eq_of_tendsto
- rightLim_eq_sInf
- rightLim_leftLim
- rightLim_rightLim
- tendsto_atBot_of_mapClusterPt
- tendsto_leftLim_atBot_of_tendsto
- tendsto_rightLim_atBot_of_tendsto
- tendsto_rightLim_of_tendsto
-- continuousWithinAt_Ioi_iff_rightLim_eq
-- le_rightLim
-- rightLim
-- rightLim_le
-- tendsto_rightLim
-- tendsto_rightLim_within

You can run this locally as follows

## from your `mathlib4` directory:
git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci

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

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

The doc-module for scripts/pr_summary/declarations_diff.sh in the mathlib-ci repository contains some details about this script.

Declarations diff (Lean -- stale, waiting for the new build)

✅ Lean-aware diff — post-build, computed from the Lean environment (commit 1580de7).

• +0 new declarations
• −0 removed declarations

No declaration differences.

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No changes to strong technical debt.
No changes to weak technical debt.

Current commit e4213d57a1
Reference commit 156b4fb350

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.py 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).

[JovanGerb]

Thanks for giving this a go