fix: when parse_* is false, add RAW nodes to AST

[bartveneman]

closes #154

• src/parse.ts: Selector fallback now creates a RAW node when
  parse_selectors_enabled is false, instead of always using SELECTOR_LIST
• src/parse-declaration.ts: Added RAW import and an else branch that creates a
  RAW node as a child of DECLARATION when value_parser is null (parse_values:
  false)
• src/css-node.ts: Updated the value getter to only return first_child when
  it's a VALUE node (not RAW), keeping declaration.value returning the raw text
  string when parse_values: false
• src/parse-options.test.ts: Updated 9 test assertions — has_children: false →
  true for parse_values:false cases, SELECTOR_LIST → RAW for
  parse_selectors:false cases, plus added first_child?.type === RAW assertion
• src/walk.test.ts: Updated 19 expected type arrays — SELECTOR_LIST → RAW for
  all parse_selectors: false cases, and added RAW after DECLARATION for all
  parse_values: false cases

some extras

• expose ATTR_FLAG_NAMES and ATTR_OPERATOR_NAMES publicly

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.92%. Comparing base (00b8452) to head (2e6e133).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #155   +/-   ##
=======================================
  Coverage   94.91%   94.92%           
=======================================
  Files          16       16           
  Lines        2793     2797    +4     
  Branches      736      736           
=======================================
+ Hits         2651     2655    +4     
  Misses        142      142           

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[codecov-commenter]

Bundle Report

Changes will increase total bundle size by 532 bytes (0.35%) ⬆️. This is within the configured threshold ✅

Detailed changes

Bundle name	Size	Change
@projectwallace/css-parser-esm	150.65kB	532 bytes (0.35%) ⬆️

Affected Assets, Files, and Routes:

view changes for bundle: @projectwallace/css-parser-esm

Assets Changed:

Asset Name	Size Change	Total Size	Change (%)
parse-*.js	206 bytes	7.36kB	2.88%
css-*.js	36 bytes	16.29kB	0.22%
parse.js	210 bytes	13.71kB	1.56%
arena.js	20 bytes	11.07kB	0.18%
constants.js	17 bytes	2.1kB	0.82%
index.js	43 bytes	1.94kB	2.27%

Files in parse-*.js:

• ./src/parse-declaration.ts → Total Size: 6.7kB

Files in css-*.js:

• ./src/css-node.ts → Total Size: 15.13kB

Files in parse.js:

• ./src/parse.ts → Total Size: 12.83kB

Files in arena.js:

• ./src/arena.ts → Total Size: 10.11kB

Files in constants.js:

• ./src/constants.ts → Total Size: 707 bytes

Files in index.js:

• ./src/index.ts → Total Size: 0 bytes