feat: generate test substrait plans & basic parse

[Rich-T-kid]

No description provided.

[Copilot]

Pull request overview

This PR adds high-level architectural comments to the substrait package, outlining the planned workflow for processing Substrait plans: converting raw bytes to plans, parsing to an AST, optimizing, and executing operators. The comments serve as a roadmap for future implementation.

• Added architectural comments documenting the planned workflow for Substrait plan processing

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[Copilot]

These comments should follow Go documentation conventions: start with a capital letter and end with a period. Additionally, "in memory" should be hyphenated as "in-memory" when used as a compound adjective. The trailing empty comment line (line 7) should be removed as it serves no purpose.

Suggested format:

// Turn raw bytes to substrait plan.
// Parse substrait plan to in-memory format we can work with (abstract syntax tree).
// Optimize the plan (apply optimizations).
// Run operators based on the optimized plan.

Suggested change

	// turn raw bytes to substrait plan
	// parse substrait plan to in memory format we can work with (abstract syntax tree)
	// optimize the plan (apply optimizations)
	// run operators based on the optimized plan
	//
	// Turn raw bytes to substrait plan.
	// Parse substrait plan to in-memory format we can work with (abstract syntax tree).
	// Optimize the plan (apply optimizations).
	// Run operators based on the optimized plan.

[Copilot]

The hyphenation "in memory" should be "in-memory" when used as a compound adjective modifying "format".

Suggested change

	// parse substrait plan to in memory format we can work with (abstract syntax tree)
	// parse substrait plan to in-memory format we can work with (abstract syntax tree)