feat: make the arguments print themselves with type info

[systay]

Description

Currently, arguments are sent as a map to the vttablet, which then incorporates them into the query string using literals. This method works well for types with robust literal support but poses issues for types that do not, such as dates and times.

This PR addresses the issue by altering the handling of types that cannot be easily represented as literals. For these types, we will now use strings and the CAST function to convert them into the correct type within the query, ensuring the values are correctly interpreted by the database.

Example:

The query that triggered this work was:

select (select sum(length(foo)) from tbl1) as X from tbl2

This would be split up into two different queries:

select sum(length(foo)) from tbl1;

# and the second query

select :sq1 as X from tbl2

If the first query returns a decimal value of 50, the second query becomes:

select 50 as X from tbl2

This converts the value to a bigint, not a decimal, which is unexpected.

Related Issue(s)

Fixes #16261

Checklist

• "Backport to:" labels have been added if this change should be back-ported to release branches
• If this change is to be back-ported to previous releases, a justification is included in the PR description
• Tests were added or are not required
• Did the new or modified tests pass consistently locally and on CI?
• Documentation was added or is not required

[vitess-bot]

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[codecov]

Codecov Report

Attention: Patch coverage is 51.51515% with 48 lines in your changes missing coverage. Please review.

Project coverage is 68.61%. Comparing base (fbbd036) to head (45e581a).
Report is 4 commits behind head on main.

Files	Patch %	Lines
go/vt/sqlparser/ast_format.go	15.21%	39 Missing ⚠️
...vtgate/planbuilder/plancontext/planning_context.go	0.00%	5 Missing ⚠️
.../vtgate/planbuilder/operators/subquery_planning.go	91.66%	3 Missing ⚠️
go/vt/vtgate/semantics/table_collector.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #16232      +/-   ##
==========================================
+ Coverage   68.60%   68.61%   +0.01%     
==========================================
  Files        1544     1544              
  Lines      198016   198065      +49     
==========================================
+ Hits       135849   135903      +54     
+ Misses      62167    62162       -5     

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[systay]

@dbussink would you mind reviewing this PR?

[harshit-gangal]

clearly some diff I cannot see.

[harshit-gangal]

Is this an unreachable code?

[systay]

it was not used in any of the queries we tested. this is handled pretty early in the planning process, when the subqueries are still inside a SubqueryContainer, so removing this code made no difference