perf(schema-compiler): Remove JSON.stringify in cache key hashing

[ovr]

… hashing

file.content is already a string, so JSON.stringify just allocates a full copy with added quotes before feeding it to MD5. Hashing the string directly eliminates ~12MB of throwaway allocations per compilation cycle (200 files x 4 phases), reduces GC pressure, and benchmarks 2.6x faster on the hashing hot path — freeing CPU cycles that were spent copying strings and collecting short-lived garbage.

[codecov]

Codecov Report

❌ Patch coverage is 66.66667% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 57.42%. Comparing base (884811a) to head (0cc8314).
⚠️ Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
...schema-compiler/src/compiler/DataSchemaCompiler.ts	66.66%	1 Missing ⚠️

❗ There is a different number of reports uploaded between BASE (884811a) and HEAD (0cc8314). Click for more details.

HEAD has 1 upload less than BASE

Flag	BASE (884811a)	HEAD (0cc8314)
cubesql	1	0

Additional details and impacted files

@@             Coverage Diff             @@
##           master   #10404       +/-   ##
===========================================
- Coverage   78.41%   57.42%   -20.99%     
===========================================
  Files         472      222      -250     
  Lines       92054    17368    -74686     
  Branches     3555     3555               
===========================================
- Hits        72181     9974    -62207     
+ Misses      19338     6859    -12479     
  Partials      535      535               

Flag	Coverage Δ
cube-backend	57.42% <66.66%> (ø)
cubesql	?

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