feat: define Complex.UnitDisc.shift

[urkud]

Also review the existing API

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[github-actions]

PR summary cc0ebd15d3

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference
Mathlib.Analysis.Complex.UnitDisc.Shift (new file)	1471

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Declarations diff

+ Complex.UnitDisc.coe_smul_circle
+ casesOn
+ casesOn_mk
+ coe_circle_smul
+ coe_closedBall_smul
+ coe_neg
+ coe_shift
+ coe_shiftFun
+ coe_star
+ im_star
+ instIsScalarTower_circle
+ instIsScalarTower_circle_circle
+ instIsScalarTower_closedBall
+ instIsScalarTower_closedBall_closedBall
+ instMulActionCircle
+ instMulActionClosedBall
+ instSMulCommClass_circle_left
+ instSMulCommClass_circle_right
+ instSMulCommClass_closedBall_left
+ instSMulCommClass_closedBall_right
+ instance : InvolutiveStar 𝔻
+ instance : Star 𝔻
+ instance : StarMul 𝔻
+ involutive_shift_comp_neg
+ neg_shift
+ neg_shift_neg
+ norm_shiftFun_le
+ norm_shift_le
+ norm_shift_swap
+ re_star
+ shift
+ shiftCompCoeff
+ shiftFun
+ shiftFun_eq_iff
+ shiftFun_neg_apply_shiftFun
+ shift_apply_circle_smul
+ shift_apply_neg_self
+ shift_apply_shift
+ shift_apply_shift_neg
+ shift_apply_zero
+ shift_den_ne_zero
+ shift_den_ne_zero'
+ shift_eq_iff
+ shift_eq_self_iff
+ shift_eq_zero_iff
+ shift_neg_apply_self
+ shift_neg_apply_shift
+ shift_trans_shift
+ shift_zero
+ sq_norm_lt_one
+ star_eq_zero
+ star_neg
+ star_shift
+ star_zero
+ symm_shift
+ «conj»
- circleAction
- closedBallAction
- coe_smul_circle
- conj
- conj_zero
- instSMulCommClass_circle
- instSMulCommClass_circle'
- instSMulCommClass_closedBall
- instSMulCommClass_closedBall'
- isScalarTower_circle
- isScalarTower_circle_circle
- isScalarTower_closedBall
- isScalarTower_closedBall_closedBall

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.

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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).