End-to-End Engineering System Readiness for Java V2 Libraries

**Summary**
End-to-end engineering system updates to support Java V2 libraries, including:
- Updating pipeline templates and scripts (PR, CI, batch release, patch release)
- Downstream tooling for SDK releases (`Release Plan App`, `azsdk-cli` MCP tools)
- Documentation on `learn.microsoft.com`

**Goal**
Enable reliable and consistent releases of V2 libraries with the new tag format: `GroupId+ArtifactId_Version`.

**Clarification**
V2 libraries may share the same `artifactId` but have different `groupId`.
Example: `com.azure:azure-core` vs `com.azure.v2:azure-core`.