Competitive Ruleset + QoL toggles (rebased from #196)

[JRickey]

Rebased version of #196 by @the-outcaster — adds a Competitive Ruleset toggle and several QoL settings under Settings → Gameplay:

• Use Competitive Ruleset — forces 4 stocks / 8-minute timer / items off / team attack on / Dream Land only in VS mode.
• Neutral Spawns on Dreamland — balanced 1v1 + 2v2 starting positions.
• Boot to VS CSS — skip intro, land on the VS Mode CSS at startup.
• Skip Results Screen — go straight back to CSS after a match.
• Force CPU Level 9 — auto-set all CPUs to level 9.

Decomp side

Pairs with decomp PR JRickey/ssb-decomp-re#5 (the C-side hooks). Decomp pointer bumped to d208de7b9 — that commit is the rebased version of PR #5 sitting on top of current port-patches, pushed to the agent/comp-ruleset branch on JRickey/ssb-decomp-re. After this PR merges, port-patches should be fast-forwarded to that SHA and decomp PR #5 closed.

Conflict resolution

• The original PR added its widgets just after the Hitbox View widget; ESC Menu Revamp #170 (already merged) inserts its new Input sidebar at the same spot. Resolved by placing Competitive Ruleset + QoL widgets first (they stay in the Gameplay sidebar with the existing path), then the Input sidebar transition. Functionally identical to merging them independently.

Build-verified on Windows (MSVC).

Closes #196

Co-authored-by: the-outcaster linuxgamingcentral@pm.me