feat(Topology/FiberBundle): continuousWithinAt_section and continuousAt_section

[Deicyde]

These lemmas are analogous to contMDiffWithinAt_section and contMDiffAt_section for smooth vector bundles.

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AI Use: Claude was used to help write the precise proof terms.
The overall API was designed to exactly mimic the existing contMDiff analogues.

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[github-actions]

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[github-actions]

PR summary 3be903dc33

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

+ continuousAt_section
+ continuousWithinAt_section

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.

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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).

[Deicyde]

easy

[grunweg]

Thanks for the PR! I have slightly different proof terms in mind --- my take-away is to look at the analogous proof to see if there are improvements to be had.

[grunweg]

In general, it's a good idea to compare with the analogous proof, to see which version is better.
I find simp_rw [continuousWithinAt_totalSpace, and_iff_right_iff_imp]; intro; exact continuousWithinAt_id slightly nicer.

[grunweg]

This proof reduces to the withinAt version, which is often a good idea:

Suggested change

	continuousAt_totalSpace (F := F) _ |>.trans (and_iff_right continuousAt_id)
	simp_rw [← contMDiffWithinAt_univ]; exact contMDiffWithinAt_section