#4291 rules parser updates

[cielbellerose]

Changes

• FHE now catches subrules with format "(a)" instead of just "a."

• Removed TOC exclusion, the formatting was just too hard to perfect and I didn't want the chance of excluding any rules. Users now have the option to specify a first page to skip over the beginning pdf sections

• Removed automatic header/footer exclusion, the logic was too specific/unreliable and risked removing real rule content

Test Cases

Added parsing test coverage!

• Excluding page number footer tests ('Page 7 of 143' for FSAE, '7' individual numbers for FHE)
• normalizeContent???
• findParentRuleCode testing ('EV.5.2.2' -> 'EV.5.2')
• handleDuplicateCodes adds suffix correctly
• extractSubRules for a, b, c rules captured only when on new line
• FSAE and FHE test coverage with real pdf examples

Screenshots

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Closes #4291