Add specs for include bracket/dot access, liquid tag, and multiline if

[Maaarcocr]

Add specs for include bracket/dot access, liquid tag, and multiline if

Adds 60 new recorded test specs across three new spec files, covering edge cases and parity tests for three areas of the Liquid spec.

New spec files

specs/liquid_ruby/include_bracket_dot.yml (5 specs)
Covers {% include %} with bracket and dot notation in argument expressions, e.g. data[config.key].values. Also includes or conditions combined with blank/empty comparisons.

specs/liquid_ruby/liquid_tag.yml (48 specs)
Comprehensive parity tests for the {% liquid %} tag, covering the full range of constructs that can appear inside it:

• assign, echo, capture
• if/elsif/else/unless with complex boolean conditions (and/or)
• for/else, break/continue
• case/when/else (including nested inside if and for)
• cycle, tablerow, ifchanged
• increment/decrement
• comment blocks and # inline comments
• render inside liquid tag

specs/liquid_ruby/multiline_if.yml (7 specs)
Tests for multi-condition if expressions with mixed and/or operators, including comparisons and deep property lookups (e.g. a.b.c).