Avoid rewriting unsharded queries and split semantic analysis in two

[frouioui]

Description

In a recent PR, we introduced a column alias expansion that has lead to a few users running into issues.
The idea with the column expansion was to make everything cleaner and simpler for the planner. In the cases where the planner was not involved (queries to a single unsharded keyspace), this however lead to problems.

With this PR, we change the semantic analysis and the early rewriter so that we do minimal work on the query when we don't need it.

In the early phase of the analyzer, we go over tables in FROM clauses, and see if any of them needs additional planning. If after this step we know that we don't need to plan the query, we are done and finish early, bypassing a lot of steps that are not necessary.

Related Issue(s)

PR that introduced the bug: #14935

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

Deployment Notes

[vitess-bot]

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[GrahamCampbell]

Do we need to backport this to 18 and 19?

[harshit-gangal]

unit test are failing

[codecov]

Codecov Report

Attention: 5 lines in your changes are missing coverage. Please review.

Comparison is base (a0ce8bc) 67.43% compared to head (f44bfce) 67.44%.
Report is 1 commits behind head on main.

Files	Patch %	Lines
go/vt/vtgate/semantics/analyzer.go	96.00%	3 Missing ⚠️
go/vt/vtgate/planbuilder/operators/hash_join.go	0.00%	1 Missing ⚠️
go/vt/vtgate/semantics/semantic_state.go	75.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff            @@
##             main   #15217    +/-   ##
========================================
  Coverage   67.43%   67.44%            
========================================
  Files        1560     1560            
  Lines      192789   192899   +110     
========================================
+ Hits       130014   130099    +85     
- Misses      62775    62800    +25     

☔ View full report in Codecov by Sentry.
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[harshit-gangal]

There is still an issue with the routing

{
        "from_table": "ps.route2",
        "to_tables": [
          "main.unsharded"
        ]
      },

{
          "QueryType": "SELECT",
          "Original": "select * from ps.route2 where id > 2",
          "Instructions": {
            "OperatorType": "Route",
            "Variant": "Unsharded",
            "Keyspace": {
              "Name": "ps",
              "Sharded": false
            },
            "FieldQuery": "select * from unsharded as route2 where 1 != 1",
            "Query": "select * from unsharded as route2 where id > 2",
            "Table": "unsharded"
          },
          "TablesUsed": [
            "ps.unsharded"
          ]
        }

This is being sent to the wrong keyspace

[systay]

There is still an issue with the routing
...
This is being sent to the wrong keyspace

This hasn't changed with this PR. The same thing happens on main