[AIT-73302] Align ACP 4.5 version and upgrade documentation

[chinameok]

Summary

• forward-port the stable support, HCP, operating-system, and upgrade guidance reviewed in [AIT-73302] Align ACP 4.4 version and upgrade documentation #993 to the future ACP 4.5 documentation
• add ACP 4.5 to the Kubernetes Support Matrix with Kubernetes 1.36 for cluster creation and 1.36 through 1.33 as Compatible Versions
• document the ACP 4.5 n-3 minor upgrade window while keeping exact patch eligibility governed by availableUpdates and VersionUpgradePath
• centralize third-party cluster product validation scope and keep its currently validated Kubernetes range separate from platform-managed cluster support
• remove release-specific wording from stable upgrade procedures and route Alauda OS workflows to immutable-infra-docs

Version boundaries

• ACP 4.5 platform-managed cluster creation: Kubernetes 1.36
• ACP 4.5 Compatible Versions: Kubernetes 1.36, 1.35, 1.34, and 1.33
• ACP 4.5 minor-level direct upgrade sources: ACP 4.2, 4.3, and 4.4
• ACP 4.1 and earlier require an intermediate path offered by the platform
• third-party cluster product-tested onboarding remains Kubernetes 1.28 through 1.35 until additional product validation is completed and documented

Validation

• yarn lint
• yarn build
• git diff --check

Related release-4.4 documentation review: #993

Jira: https://jira.alauda.cn/browse/AIT-73302