Fix convention-level ignore for filter operations

[michaelstaib]

• propagate ignored filter operation fields from convention extensions into merged filter input definitions
• preserve operation field configurations marked as ignored so merge logic can apply them
• add a regression test proving Configure<StringOperationFilterInputType>(...Operation(...).Ignore()) removes operations from the schema

Fixes #5406.

[github-actions]

Fusion Gateway Performance Results

Simple Composite Query

	Req/s	Err%
Constant 2 (50 VUs)	4155.75	0.00%
Ramping 2 (0-500-0 VUs)	3969.48	0.00%

Response Times

	Min	Med	Avg	P90	P95	Max
Constant 2	0.97ms	9.53ms	11.82ms	19.49ms	27.58ms	241.82ms
Ramping 2	1.06ms	48.92ms	54.90ms	96.46ms	144.38ms	314.10ms

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Deep Recursion Query

	Req/s	Err%
Constant 2 (50 VUs)	716.01	0.00%
Ramping 2 (0-500-0 VUs)	772.34	0.00%

Response Times

	Min	Med	Avg	P90	P95	Max
Constant 2	11.64ms	60.52ms	67.65ms	87.36ms	104.92ms	656.60ms
Ramping 2	3.09ms	240.52ms	265.21ms	551.60ms	616.49ms	954.76ms

---

Variable Batching Throughput

	Req/s	Err%
Constant 2 (50 VUs)	5968.76	0.00%
Ramping 2 (0-500-0 VUs)	5258.02	0.00%

Response Times

	Min	Med	Avg	P90	P95	Max
Constant 2	0.16ms	7.83ms	8.28ms	13.74ms	16.76ms	67.37ms
Ramping 2	0.19ms	39.10ms	43.68ms	81.47ms	105.94ms	215.76ms

---

Runner 2 = benchmarking-2

Run 22417096947 • Commit 25d9d6d • Wed, 25 Feb 2026 22:12:45 GMT