refactor(Analysis): golf Mathlib/Analysis/Normed/Module/Dual

[yuanyi-350]

• rewrites polar_ball in Analysis/Normed/Module/Dual to deduce the result from polar_closure, closure_ball, and polar_closedBall instead of proving both inclusions by hand

Extracted from #37968

[yuanyi-350]

!bench

[leanprover-radar]

Benchmark results for 948b83f against 9268b22 are in. No significant results found. @yuanyi-350

• 🟥 build//instructions: +33.3G (+0.02%)

Small changes (4✅, 2🟥)

• ✅ build/module/Mathlib.Analysis.Normed.Module.Dual//instructions: -1.2G (-5.04%)
• 🟥 build/module/Mathlib.Combinatorics.Quiver.Path.Decomposition//instructions: +359.9M (+6.45%)
• 🟥 build/module/Mathlib.MeasureTheory.MeasurableSpace.Card//instructions: +436.5M (+3.63%)
• ✅ build/module/Mathlib.Tactic.Attr.Core//instructions: -391.4M (-14.07%)
• ✅ build/module/Mathlib.Tactic.MkIffOfInductiveProp//instructions: -382.2M (-3.85%)
• ✅ build/module/Mathlib.Util.AtLocation//instructions: -138.5M (-3.17%)

[github-actions]

PR summary 9268b22206

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):

• NormedSpace.polar_ball: 0.534572 -> 0.082561 (-84.56%)

Overall:

• the rewritten proof is substantially faster than the previous inclusion-by-inclusion argument.