Caller-supplied identifiers now percent-encoded in URLs

Changes since sdk==0.3.14

• release(checkpoint): 4.1.1 (#7890)
• release(sdk-py): 0.3.15 (#7891)
• fix(sdk-py): percent-encode caller-supplied identifiers in URL paths (#7893)
• release(langgraph): 1.2.1 (#7883)
• chore(deps): bump idna from 3.11 to 3.15 in /libs/sdk-py (#7863)
• chore(deps): bump urllib3 from 2.6.3 to 2.7.0 in /libs/sdk-py (#7764)
• chore(deps): bump langsmith from 0.7.31 to 0.8.0 in /libs/sdk-py (#7789)
• release: bump alpha packages to official versions (#7775)
• chore(langgraph): bump langchain-core to 1.4.0 (#7767)
• feat(sdk-py): support metadata filter for crons search/count (#7737)
• chore(deps): bump ty from 0.0.23 to 0.0.33 in /libs/sdk-py (#7666)