feat: add withdraw function

[JohnGuilding]

Description

Re-add withdrawal function with changes

• Add withdraw function that can be called after a cooldown
• Funds can only be sent to a preconfigured custodian (Can set this to a gitcoin wallet for production deploy) - this balances having an escape hatch, while also reducing trust assumptions of the owner.
• Can call withdraw only after tallying is complete

Minor simplifications

• Removes depositWindow not essential as deposits can stop after tallying is complete
• Removes pause functionality - no longer needed as this contract will be audited

Other changes

• Remove duringDepositWindow & afterDepositWindow modifiers
• claim can be called directly after tallying finishes

Additional Notes

Related issue(s)

Confirmation

Important

We do not accept minor grammatical fixes (e.g., correcting typos, rewording sentences) unless they significantly improve clarity in technical documentation. These contributions, while appreciated, are not a priority for merging. If there is a grammatical error feel free to message the team.

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[NicoSerranoP]

I think this PR did not git pull from main. It might be better to do that and create another PR

[0xmad]

@JohnGuilding thanks, just one question and improvement

[0xmad]

@JohnGuilding thanks!