doc: attach "pre", "pseudo", "semi" and "sub" as a prefixes where they are now free-standing

[harahu]

These are all examples of bound morphemes and should be attached, either in closed form or by hyphen, to some other construct.

Whether to write the resulting words in closed form or with a hyphen is a stylistic choice and I am open to discussing the specifics, should that be of interest. I've made choices based on existing literature and what I personally found natural, but other opinions are welcome.

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[github-actions]

PR summary 39996ca4db

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

No declarations were harmed in the making of this PR! 🐙

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).

[mathlib4-merge-conflict-bot]

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