dx: Add additional hooks to pre-commit

[s373nZ]

Adds additional hooks to pre-commit.

• The official shellcheck hook.
• Re-implements make check-amount-access as a local pygrep hook.
• Implements a clang-format hook to fail on suggestion warnings with additional configuration to sort includes.
• Re-implements make check-discouraged-functions as a local pygrep hook.

Adding this PR (along with future hooks to come) against your PR for now, until ElementsProject#7884 is merged.

[s373nZ]

Added an implementation of the make check-amount-access check. Demonstrates a locally defined hook using pygrep and therefore the regex has been converted from piped grep commands into Python format.

[s373nZ]

Added an initial version of a clang-format check. Default behavior is to do in-place editing of the files, but that is overridden and suggestion warnings are reported as errors to force a failure. Output in this fashion isn't exactly easy to see the full context of the suggestion, but one can run the full checks and inspect a diff for more of an overview.

Noticed an existing config in .clang-format and added additional instruction to sort #includes in hopes of eventually replacing make check-src-include-order and make check-hdr-include-order.

Also probably needs some more attention around which files to exclude, in accordance with the SRC_TO_CHECK and ALL_NONGEEN_HEADERS definitions in the Makefile.

[s373nZ]

Added an implementation of the make check-discouraged-functions check, also as a Python regex. There might be another static analysis tool that could also do this (and more?).

[s373nZ]

• Cleaned up regex syntax for earlier hooks.
• Added codespell to check spelling.

[s373nZ]

• Added check-jsonschema hooks to validate doc/ JSON schemas and native pre-commit hook for pretty formatting.

[s373nZ]

• Added conventional commit linting for commit messages. Looks like the also gets processed by codespell.

Grabbed the list of "scopes" from top level directory organization, along with a sane perusal of the commit messages from the last few months. Needs some auditing.

This hook utilization requires running pre-commit install --hook-type commit-msg. Would be cool to brainstorm a way to bootstrap the contributor environment with one command, like a Makefile target or script, if possible.