[router] add postgres databases data connector

[lengrongfu]

Motivation

#10341

Postgres data store provider.

Modifications

Accuracy Tests

requerment: we need a postgres database, and create a name is sql_router db.

1. start sgl-router use this pararm

$ sglang-router  --backend openai --worker-urls http://10.20.100.240:31896 --history-backend postgres --postgres-db-url postgres://postgres:xxxxx@xxxx:xxxx/sql_router?sslmode=prefer

2. call /api/response api

 curl -X POST "http://127.0.0.1:30000/v1/responses" \
  -H "Content-Type: application/json" \
  --data '{
    "model": "Qwen/Qwen3-0.6B",
    "input": "Tell me a three sentence bedtime story about a unicorn.",
    "safety_identifier": "test123"
  }

3. api can success, and to check database. we can found have create table and insert response data.

Benchmarking and Profiling

Checklist

• Format your code according to the Format code with pre-commit.
• Add unit tests according to the Run and add unit tests.
• Update documentation according to Write documentations.
• Provide accuracy and speed benchmark results according to Test the accuracy and Benchmark the speed.

[lengrongfu]

this ci error, i should how to fix? @slin1237 i whether miss code change?

[lengrongfu]

@slin1237 @key4ng hi, can help review this pr, thanks ~

[key4ng]

I'm assumnig postgres db_url contains password? if so, we should not log it

[lengrongfu]

change to: Initializing data connector: Postgres (db_url: postgres://postgres:****@127.0.0.1:3306/sql_router?sslmode=prefer, pool_max: 16)

[key4ng]

thanks for the pr. overall looks good to me, just need some minor changes.
In the future, we can also consider adding CI test for postgres db

[key4ng]

typo

Suggested change

	return Err("is it db-url should be not empty".to_string());
	return Err("db-url must not be empty".to_string());