docs: add and improve examples of connections, queries and more

[wellwelwel]

Documentation 📝

Adding examples of the most common methods and simple queries (such as CRUD).

I don't intend to interfere in the documentation itself, but I plan to contribute with some examples, including simplifying TypeScript compilation tests to reuse as examples (JS).

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Prepared Statement examples:

Both promise and callback.

execute(sql, values)

• INSERT
• SELECT
• UPDATE
• DELETE

execute(options)

• INSERT
• SELECT
• UPDATE
• DELETE

execute(options, values)

• INSERT
• SELECT
• UPDATE
• DELETE

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Simple queries examples:

Both promise and callback.

query(sql)

• INSERT
• SELECT
• UPDATE
• DELETE

query(options)

• INSERT
• SELECT
• UPDATE
• DELETE
• Include an example using rowAsArray

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Connections

Both promise and callback.

createConnection

• createConnection(connectionUri)
• createConnection(config)
• createConnection(config) — SHA1
• createConnection(config) — SSL
• createConnection(config) — RDS SSL
• createConnection(config) — Socks
  • Only callback

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createPool

• createPool(connectionUri)
• createPool(config)
• createPool(config) — SHA1
• createPool(config) — SSL
• createPool(config) — RDS SSL
• createPool(config) — Socks
  • Only callback

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createPoolCluster

• add(group, connectionUri)
• add(group, config)
• add(group, config) — SHA1
• add(group, config) — SSL
• add(group, config) — RDS SSL
• add(group, config) — Socks
  • Only callback

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And more "chore" 🧑🏻‍🔧

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Website 🔬

• Add unit tests to website's helpers
• Fix website's package-lock.json conflict between local development and dependabot
• Extract methods as string to reuse in specifications (inspired by https://tsdocs.dev)
  • It will prevent possible differences between the documentation and the source code.
• Document the ExternalCodeEmbed component
• Restrict extensions to mdx and json in the "docs" and "i18n" directories.
• Check for broken links
• Include new tests to CI