Move effect deps to implementation getter and require array return

[Copilot]

Closes #

📝 Description

Effect dependencies now belong to the effect implementation itself and must be returned via a deps getter that always yields an array, simplifying descriptors to type only.

⛳️ Current behavior (updates)

Effect descriptors could carry deps, and dependency resolvers accepted optional/undefined returns, requiring extra defensive logic.

🚀 New behavior

• Core: EffectDeps is a required getter (params) => EffectDepsValue[]; descriptors remain type-only.
• Framework runtimes: dependency resolution calls the implementation’s deps getter directly (no undefined fallback) across React, Preact, Solid, Svelte, Vue, Vanilla.
• Tests remain valid under the stricter contract.

Example:

const syncCount: EffectImpl<any> = ({ context }) => {
  // effect body
}
syncCount.deps = ({ context }) => [context.get("count")]

effects: ["syncCount"]
implementations: { effects: { syncCount } }

💣 Is this a breaking change (Yes/No):

Yes — deps must now be supplied on the implementation via a required getter; effect descriptors no longer accept deps.

📝 Additional Information

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