Highlight all PEP-0350 defined codetags

Nobody has claimed this yet.

MagicPython currently only highlights a very small subset of the codetags from [PEP-0350](https://peps.python.org/pep-0350/):

- NOTE: A note
- XXX: Attention
- HACK: A hack
- FIXME: Problematic code
- BUG: A bug
- TODO: Pending task

I think the full list should be included in MagicPython, or at least the rest of the top-level mnemonics:

- NOBUG
- REQ
- RFE
- IDEA
- ???
- !!!
- PORT
- CAVEAT
- FAQ
- GLOSS
- SEE
- TODOC
- CRED
- STAT
- RVD

* **Editor name and version**: Visual Studio Code v1.66.2
* **Platform**: Windows 10.0.19044
* **Color scheme**: Dracula
* **MagicPython version**: 1.1.0
* **A sreenshot**:
* **5-10 lines of surrounding code**: Exhaustive list of mnemonics:
```python
"""
## Supported:
NOTE: A note
XXX: Attention
HACK: A hack
FIXME: Problematic code
BUG: A bug
TODO: Pending task

## Not supported:
MILESTONE:
MLSTN:
DONE:
YAGNI:
TBD:
TOBEDONE:
DEBUG:
BROKEN:
REFACTOR:
REFACT:
RFCTR:
OOPS:
SMELL:
NEEDSWORK:
INSPECT:
BUGFIX:
NOBUG:
NOFIX:
WONTFIX:
DONTFIX:
NEVERFIX:
UNFIXABLE:
CANTFIX:
REQ:
REQUIREMENT:
STORY:
RFE:
FEETCH:
NYI:
FR:
FTRQ:
FTR:
IDEA:
???:
QUESTION:
QUEST:
QSTN:
WTF:
!!!:
ALERT:
CLEVER:
MAGIC:
PORT:
PORTABILITY:
WKRD:
CAVEAT:
CAV:
CAVT:
WARNING:
CAUTION:
HELP:
FAQ:
GLOSS:
GLOSSARY:
SEE:
REF:
REFERENCE:
TODOC:
DOCDO:
DODOC:
NEEDSDOC:
EXPLAIN:
DOCUMENT:
CRED:
CREDIT:
THANKS:
STAT:
STATUS:
RVD:
REVIEWED:
REVIEW:
"""
```

Start by locating MagicPython's existing codetag highlighting definitions and compare them with the PEP-0350 mnemonic list in the issue. Extend the recognized list to cover the requested top-level mnemonics, then run the project's syntax-highlighting tests or inspect highlighted Python comments to verify the new tags.

Written by the indexing model from the issue text.