Post events at the execution level and horde them in the inspector

[BonelessImpl]

No description provided.

[fusede]

It's up to implementation whether to emit event, store it somewhere internally or handle it in some another way:

Suggested change

	fn emit_event(&mut self, event: DefuseEvent<'_>);
	fn on_event(&mut self, event: DefuseEvent<'_>);

[fusede]

This way it will only be possible to emit dip4 events, but not nep245 and others...
Can you make it accept all possible events that we might have in some structured way? E.g. by accepting Event enum as parameter:

#[serde(untagged)]
 pub enum Event<'a> {
    Dip4(DefuseEvent<'a>),
    Nep245(MtEvent<'a>),
    // ...
}

impl Event<'_> {
    pub fn emit(&self) {
        match self {
            Self::Dip4(event) => event.emit(),
            Self::Nep245(event) => event.emit(),
        }
    }
}

The complex part will be to re-write Contract::deposit() and Contract::withdraw methods, so that they become Inspector-aware, or, in general, intent-aware... Or maybe you have other suggestions?

[fusede]

Make it more convenient for callers to avoid parsing strings as JSON:

Suggested change

	pub events_emitted: Vec<String>,
	pub events: Vec<serde_json::Value>,

[fusede]

Or it would be even better if we don't bind to JSON specifically, but use strongly-typed Event struct/enum...

[BonelessImpl]

Push event objects presents a challenge because the values are mostly references. In fact, I changed some Cow::Borrow to Owned to make this work. If we get rid of references, then this is easily doable.

[fusede]

Suggested change

	pub events_emitted: Vec<serde_json::Value>,
	pub events: Vec<serde_json::Value>,

[BonelessImpl]

Closed in favor of #91