[Merged by Bors] - chore: make CLM.extend total and define LM.leftInverse

[mcdoll]

• Make ContinuousLinearMap.extend a total function
• Define LinearMap.leftInverse as a total function with junk value if the input is not invertible.

Required for #31074

---

[github-actions]

PR summary 6a54a80825

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

---

Declarations diff

+ LinearMap.leftInverse
+ LinearMap.leftInverse_apply_of_inj
+ LinearMap.leftInverse_comp_of_inj
+ SimpleFunc.integralCLM'_L1_eq_integral
+ integral_eq'
+ setToL1'_apply_coeToLp
+ setToL1'_eq_setToL1SCLM
+ setToL1_apply_coeToLp
+ setToL1_unique

You can run this locally as follows

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

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

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

---

No changes to technical debt.

You can run this locally as

./scripts/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).

[j-loreaux]

Thanks for putting the effort into this Moritz! Yes, I think this is the way to go for ContinuousLinearMap.extend and hence for convenience constructor variation too.

[j-loreaux]

bors merge

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

• Build
• Post-Build Step
• Lint style