Audit Fixes - System Changes - Code Refactoring - Mega Merge

[GalloDaSballo]

Mega PR of all changes

5.1 -> WIP

Fix: 5.2 - Try Catch that actually doesn't revert - https://github.com/liquity/V2-gov/pull/5

• [x] Fix known vector such as: selfdestruct, returnbomb, gasgrief and reverts
• [ ] Discuss Gas to Hooks
• [x] Basic Tests
• [ ] Invariant Testing on Governance to prevent any DOS | cc: @nican0r | High impact | Mid Prio
• [ ] Invariant Testing Setup to test Initiatives to verify if they are safe to use | cc: @nican0r | Low Prio | High Impact

Fix: 5.3 - fix: counted ts fix - https://github.com/liquity/V2-gov/pull/18

• [ ] Write tests to identify the bug
• [ ] Write fuzz / invariant tests to ensure the bug doesn't happen again @nican0r need coverage here pls

5.4 - WIP - See: https://github.com/liquity/V2-gov/pull/16

5.5 - WIP - CC: @nican0r

Fix: 5.6 - see 5.2

5.7 -> See 5.4

5.8 -> See 5.4

Fix: 5.9 - Curve Claim Flow + Tests + Griefing - https://github.com/liquity/V2-gov/pull/10

• [ ] Needs true E2E Forked Tests

5.10 -> See 5.4

5.11

Awaiting @jltqy See: fix/voteCheck May rewrite these

5.12

Ack -> TODO: Review Game Theory

Rest

• TODO Later

---

Pending

NOT MERGED - Fix: V4 Claim Grief Flow - https://github.com/liquity/V2-gov/pull/11

• [ ] Does the hook work?
• [ ] Does the vesting work
• [ ] E2E Fork Test

Minor

Unchecked ETH Transfer - https://github.com/liquity/V2-gov/pull/7

• [X] Adds a check
• [ ] Should we allow specifying a different recipient?

Always use safeTransfer | https://github.com/liquity/V2-gov/commit/bcf897e5fcea601178b14a2973b5c6d59f7e951b

• [ ] TODO: Decide if we want to remove all of them since approve is not safe and bold and lqty don't require it