[POC] feat: storage for optimizer core objects

[yliang412]

Problem

Persistence storage is on top of the optd optimizer wishlist.

Summary of changes

This PR models the storage for optimizer core objects in SQLite using diesel-rs.

• Models core object relationships in SQL.
• use diesel-rs to codegen schema and dsl.
• Adds "new type identifiers and from/to SQL conversion (e.g. RelGroupId, RelSubGroupId, LogicalExprId, etc.).
• Add developer docs on how to use diesel-rs. Rendered

TODO:

• Add developer docs on how to add new logical, physical, and scalar operators.
• Add tests for memo table access methods.
• Separate the definition for each table into a separate file.
• Determine whether indexes are needed (or SQLite pkey is enough).

Future work

• Use the "table inheritance" pattern for logical, physical, and scalar properties.

[yliang412]

@connortsui20 Should we do build with source? The CI is probably not happy with linking with sqlite3.

On another note, do we want to install the diesel CLI on the CI images?

[yliang412]

bundled libsqlite3-sys to resolve build problems.

[yliang412]

implement part of this in #22