fix: Preserve applied IMPORT hints on importing another .sqrl script

[ferenc-csaky]

Key Changes

• Manage inherited imports on planMain
• Apply inherited imports if there are any when we create PlannerHints during SQRL script planning
• Added DAG planner test case to cover the inherit logic

Fixes #2102

[codecov]

Codecov Report

❌ Patch coverage is 0% with 14 lines in your changes missing coverage. Please review.
✅ Project coverage is 15.44%. Comparing base (2e44441) to head (5463c19).
⚠️ Report is 2 commits behind head on main.
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
...n/java/com/datasqrl/planner/hint/PlannerHints.java	0.00%	7 Missing ⚠️
...in/java/com/datasqrl/planner/SqlScriptPlanner.java	0.00%	6 Missing ⚠️
.../java/com/datasqrl/compile/CompilationProcess.java	0.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2178      +/-   ##
============================================
- Coverage     15.44%   15.44%   -0.01%     
  Complexity      975      975              
============================================
  Files           618      618              
  Lines         17832    17837       +5     
  Branches       2176     2177       +1     
============================================
  Hits           2755     2755              
- Misses        14807    14812       +5     
  Partials        270      270              

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