Refactor generated codes

[goccy]

Simplify auto-generated code by generics

• Use the EvalDef function to evaluate def block
• Use the EvalDefMap function to evaluate def with map expr
• Introduce a LocalValue structure to hide lock and CEL-related logic

[github-actions]

Code Metrics Report

	main (f605c26)	#82 (fb3d94d)	+/-
Coverage	65.6%	64.3%	-1.3%
Code to Test Ratio	1:0.4	1:0.5	+0.0
Test Execution Time	3m19s	3m24s	+5s

Details

  |                     | main (f605c26) | #82 (fb3d94d) |  +/-  |
  |---------------------|----------------|---------------|-------|
- | Coverage            |          65.6% |         64.3% | -1.3% |
  |   Files             |             60 |            61 |    +1 |
  |   Lines             |           8727 |          8878 |  +151 |
- |   Covered           |           5724 |          5708 |   -16 |
+ | Code to Test Ratio  |          1:0.4 |         1:0.5 |  +0.0 |
  |   Code              |          25503 |         24715 |  -788 |
  |   Test              |          11161 |         11161 |     0 |
- | Test Execution Time |          3m19s |         3m24s |   +5s |

Code coverage of files in pull request scope (76.1% → 66.5%)

Files	Coverage	+/-
generator/code_generator.go	84.5%	-1.4%
grpc/federation/cel.go	0.0%	0.0%
grpc/federation/error.go	0.0%	0.0%
grpc/federation/validation.go	0.0%	0.0%

---

Reported by octocov

[shuheiktgw]

naruhodo...

[shuheiktgw]

LGTM 🙆‍♂️