feat: Support referencing individual tables from SQRL scripts in IMPORT and EXPORT

[ferenc-csaky]

Key Changes

• Improve parseScript with filterable output, so we can easily collect CREATE TABLE statements from scripts
• When an individual table is referenced from a ScriptSqrlModule, load the tables in a lazy manner (once), and return it if it's defined in the script
• Created FlinkCalciteParser and moved the Flink calcite parser init there, cause now we need that in two places
• Added proper error message when an internal table is referenced from another script
• Added DAG planner tests to cover the added logic
• Updates some usecases to cover both IMPORT and EXPORT usage

TODO

• Add test(s) for IMPORT
• Update docs

[codecov]

Codecov Report

❌ Patch coverage is 1.63934% with 60 lines in your changes missing coverage. Please review.
✅ Project coverage is 16.44%. Comparing base (f90a253) to head (c034189).
⚠️ Report is 3 commits behind head on main.
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
...in/java/com/datasqrl/loaders/ScriptSqrlModule.java	0.00%	27 Missing ⚠️
...tasqrl/engine/stream/flink/FlinkCalciteParser.java	0.00%	15 Missing ⚠️
...m/datasqrl/planner/parser/SqrlStatementParser.java	0.00%	7 Missing ⚠️
...in/java/com/datasqrl/loaders/ModuleLoaderImpl.java	0.00%	4 Missing ⚠️
...in/java/com/datasqrl/planner/SqlScriptPlanner.java	0.00%	3 Missing ⚠️
...java/com/datasqrl/loaders/DirectorySqrlModule.java	0.00%	2 Missing ⚠️
...om/datasqrl/loaders/FlinkTableNamespaceObject.java	0.00%	1 Missing ⚠️
.../com/datasqrl/planner/Sqrl2FlinkSQLTranslator.java	0.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2218      +/-   ##
============================================
- Coverage     16.47%   16.44%   -0.03%     
  Complexity     1034     1034              
============================================
  Files           622      623       +1     
  Lines         17951    17983      +32     
  Branches       2193     2197       +4     
============================================
+ Hits           2957     2958       +1     
- Misses        14689    14720      +31     
  Partials        305      305              

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