chore(Combinatorics/Enumerative/Catalan): split into Basic & Tree

[GrigorenkoPV]

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Split off from #34853

[github-actions]

PR summary ea9c91472b

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference
Mathlib.Combinatorics.Enumerative.DyckWord	1
Mathlib.Combinatorics.Enumerative.Catalan	2
Mathlib.Combinatorics.Enumerative.Catalan.Basic (new file)	808
Mathlib.Combinatorics.Enumerative.Catalan.Tree (new file)	809

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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.

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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).

[mathlib-merge-conflicts]

This pull request has conflicts, please merge master and resolve them.

[vihdzp]

This looks reasonable to me, though I'm curious, what's the motivation? Is it imports? File length? Something else?

[mathlib-merge-conflicts]

This pull request has conflicts, please merge master and resolve them.

[YaelDillies]

Thanks! 🚀

maintainer merge

[github-actions]

🚀 Pull request has been placed on the maintainer queue by YaelDillies.