perf: remove string cloning for DataPath in Synth

[meskill]

Summary:
Briefly describe the changes made in this PR.

Issue Reference(s):
Fixes #... (Replace "..." with the issue number)

Build & Testing:

• [ ] I ran cargo test successfully.
• [ ] I have run ./lint.sh --mode=fix to fix all linting issues raised by ./lint.sh --mode=check.

Checklist:

• [ ] I have added relevant unit & integration tests.
• [ ] I have updated the documentation accordingly.
• [ ] I have performed a self-review of my code.
• [ ] PR follows the naming convention of <type>(<optional scope>): <title>

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 93.33333% with 1 line in your changes missing coverage. Please review.

Project coverage is 87.21%. Comparing base (eab8326) to head (c75a889). Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/core/jit/graphql_error.rs	0.00%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #3074 +/- ## ========================================== + Coverage 87.19% 87.21% +0.01% ========================================== Files 280 280 Lines 27418 27421 +3 ========================================== + Hits 23908 23916 +8 + Misses 3510 3505 -5 ```

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[github-actions[bot]]

Bencher Report

Branch	3074/merge
Testbed	benchmarking-runner

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Benchmark	Latency	nanoseconds (ns)
from_json_bench	📈 view plot ⚠️ NO THRESHOLD	6,131,300.00
group_by	📈 view plot ⚠️ NO THRESHOLD	484.76
input/args.missing	📈 view plot ⚠️ NO THRESHOLD	28.61
input/args.nested.existing	📈 view plot ⚠️ NO THRESHOLD	43.70
input/args.nested.missing	📈 view plot ⚠️ NO THRESHOLD	38.36
input/args.root	📈 view plot ⚠️ NO THRESHOLD	37.44
input/headers.existing	📈 view plot ⚠️ NO THRESHOLD	32.68
input/headers.missing	📈 view plot ⚠️ NO THRESHOLD	31.65
input/value.missing	📈 view plot ⚠️ NO THRESHOLD	23.20
input/value.nested.existing	📈 view plot ⚠️ NO THRESHOLD	43.67
input/value.nested.missing	📈 view plot ⚠️ NO THRESHOLD	37.70
input/value.root	📈 view plot ⚠️ NO THRESHOLD	37.52
input/vars.existing	📈 view plot ⚠️ NO THRESHOLD	7.77
input/vars.missing	📈 view plot ⚠️ NO THRESHOLD	8.07
synth_nested	📈 view plot ⚠️ NO THRESHOLD	94,190.00
synth_nested_borrow	📈 view plot ⚠️ NO THRESHOLD	43,266.00
test_batched_body	📈 view plot ⚠️ NO THRESHOLD	1,903.60
test_batched_body #2	📈 view plot ⚠️ NO THRESHOLD	1,528,600.00
test_data_loader	📈 view plot ⚠️ NO THRESHOLD	385,580.00
test_handle_request	📈 view plot ⚠️ NO THRESHOLD	129,450.00
test_handle_request_jit	📈 view plot ⚠️ NO THRESHOLD	61,621.00
test_http_execute_method	📈 view plot ⚠️ NO THRESHOLD	14,825.00
with_mustache_expressions	📈 view plot ⚠️ NO THRESHOLD	1,088.90
with_mustache_literal	📈 view plot ⚠️ NO THRESHOLD	722.30

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