Add support for meta hints and some initial reader macros

[jeaye]

• Meta hints
  • [x] Keywords
  • [x] Maps
• Reader macros
  • [x] Comments
  • [x] Sets
  • [x] Conditionals (with splicing)
  • [x] Fn literals
  • [ ] Regex
  • [x] Var quote
  • Syntax quoting
  • [x] Gensyms
  • [x] Auto symbol qualification
  • [x] Unquoting
  • [x] Unquote splicing

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 85.16912% with 171 lines in your changes are missing coverage. Please review.

Project coverage is 63.86%. Comparing base (77a6655) to head (571d247).

:exclamation: Current head 571d247 differs from pull request most recent head 88ecf09. Consider uploading reports for the commit 88ecf09 to get more accurate results

Files	Patch %	Lines
src/cpp/jank/codegen/processor.cpp	31.81%	90 Missing :warning:
src/cpp/jank/read/parse.cpp	88.08%	53 Missing :warning:
src/cpp/jank/evaluate.cpp	66.66%	12 Missing :warning:
src/cpp/jank/read/lex.cpp	92.06%	5 Missing :warning:
src/cpp/jank/runtime/context.cpp	33.33%	4 Missing :warning:
src/cpp/jank/analyze/processor.cpp	94.28%	2 Missing :warning:
src/cpp/jank/runtime/obj/persistent_array_map.cpp	0.00%	2 Missing :warning:
src/cpp/jank/runtime/obj/persistent_hash_map.cpp	50.00%	1 Missing :warning:
src/cpp/jank/runtime/obj/persistent_vector.cpp	0.00%	1 Missing :warning:
src/cpp/jank/runtime/seq.cpp	92.30%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #59 +/- ## ========================================== + Coverage 60.57% 63.86% +3.28% ========================================== Files 53 53 Lines 7521 8579 +1058 ========================================== + Hits 4556 5479 +923 - Misses 2965 3100 +135 ```

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