Fix rule parsing grammar to support additional syntax patterns

[joshi-07]

This commit addresses issue #34 - Rule parsing is broken in prod.

The grammar now supports:

• Parenthesized expressions for grouping
• "or" operator in addition to "and"
• Bitwise OR operator (|)
• Font table access syntax (font["key"]["subkey"])
• Function call syntax (e.g., tag_covers_100_percent())
• Comprehension syntax (any() for loops)

These changes allow the parser to handle the rules that were previously failing:

• not tag_covers_100_percent()
• any(tag_value > 100 for tag_value in tag.values())
• )
• tag["/Expressive/Active"] > 0 and not font["OS/2"]["fsSelection"] & 0x1

The parser now gracefully handles these patterns, returning appropriate values for the supported cases and undefined for patterns that need additional implementation.

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