Add support for GPML-style graph query parsing

[jpschorr]

This adds addtional features to the draft parser/AST support for a subset of GPML as outlined by Graph Pattern Matching in GQL and SQL/PGQ.

The targeted language definition is what was proposed in RFC-0025 and RFC-0033.

Added by this PR:

• basic and abbreviated node and edge patterns (section 4.1 of the GPML paper)
• concatenated path patterns (section 4.2 of the GPML paper)
• path variables (section 4.2 of the GPML paper)
• graph patterns (i.e., comma separated path patterns) (section 4.3 of the GPML paper)
• AST support for path quantifiers (section 4.4 of the GPML paper)
• parenthesized patterns (section 4.4 of the GPML paper)
• parsing support for path quantifiers (section 4.4 of the GPML paper)
• restrictors and selector (section 5.1 of the GPML paper)
• parsing support for pre-filters and post-filters (section 5.2 of the GPML paper)
• AST support for pre-filters (section 5.2 of the GPML paper)

GPML features not yet implemented:

• group variables (section 4.4 of the GPML paper)
• path pattern union and multiset (section 4.5 of the GPML paper)
• conditional variables (section 4.6 of the GPML paper)
• graphical predicates (section 4.7 of the GPML paper)
• aggregates of unbounded variables (section 5.3 of the GPML paper)

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Reviving #148

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov]

Codecov Report

Attention: Patch coverage is 90.76087% with 34 lines in your changes missing coverage. Please review.

Project coverage is 81.91%. Comparing base (24ab5bd) to head (440d5ac).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
partiql-ast/src/visit.rs	66.66%	12 Missing ⚠️
partiql-common/src/pretty.rs	50.00%	9 Missing ⚠️
partiql-ast/src/pretty.rs	95.62%	6 Missing and 2 partials ⚠️
partiql-parser/src/lexer/partiql.rs	55.55%	4 Missing ⚠️
...sion/partiql-extension-visualize/src/ast_to_dot.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #548      +/-   ##
==========================================
+ Coverage   81.78%   81.91%   +0.13%     
==========================================
  Files         106      106              
  Lines       22037    22386     +349     
  Branches    22037    22386     +349     
==========================================
+ Hits        18022    18337     +315     
- Misses       3504     3536      +32     
- Partials      511      513       +2     

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[github-actions]

Conformance comparison report

	Base (24ab5bd)	2d1f652	+/-
% Passing	87.15%	87.15%	0.00%
✅ Passing	5603	5603	0
❌ Failing	826	826	0
🔶 Ignored	0	0	0
Total Tests	6429	6429	0

Number passing in both: 5603

Number failing in both: 826

Number passing in Base (24ab5bd) but now fail: 0

Number failing in Base (24ab5bd) but now pass: 0

[alancai98]

Will some more tokens be added as non-reserved in the future?

[jpschorr]

That is, generally, the nature of non-reserved tokens. If you add a new token to the grammar (generally in a subset that didn't exist before), that was previously able to be used as, e.g., a name, then this is a way to handle it.

[alancai98]

does the GPML paper require the k be non-zero? perhaps it's non-sensical to have a k of 0?

[jpschorr]

The shortest 0 paths are the empty set.