Establish common special syntax for `sql` values

[emmnull]

In some cases, ideal sql values naming can conflict with js values, that is to say that for obvious reasons we currently rely on things like

// Not allowed
// const true = sql<true>`true`;

const tru = sql<true>`true`;

At the moment, conflicting names are resolved by using arbitrary strategies, this can lead to an unintuitive DX. Moreover, having a clear consistent syntax for sql values could help users spot them through code, and adopting a prefix-approach could let users rely more efficiently on auto-completion to figure out available values.

In light of this, it could be beneficial to adopt a prefix syntax, something like:

const $true = sql<true>`true`;

A foreseeable caveat is that we opt for a syntax that ends up conflicting with some framework-specific preprocessor (ex.: svelte's $ syntax for stores although this doesn't matter as it's geared towards client-side reactive code unlike drizzle's server-side target, and is soon to be deprecated with svelte 5...)